diff --git a/src/common/gamecode/economy.c b/src/common/gamecode/economy.c
index 8a8c0db91..1d59c7b85 100644
--- a/src/common/gamecode/economy.c
+++ b/src/common/gamecode/economy.c
@@ -3066,7 +3066,7 @@ expandwork(region * r, request * work_begin, request * work_end, int maxwork)
       blessedharvest_ct = ct_find("blessedharvest");
     }
     if (blessedharvest_ct) {
-      int happy = curse_geteffect(get_curse(r->attribs, blessedharvest_ct));
+      int happy = (int)curse_geteffect(get_curse(r->attribs, blessedharvest_ct));
       happy = MIN(happy, jobs);
       earnings += happy;
     }
diff --git a/src/common/gamecode/items.c b/src/common/gamecode/items.c
index 2c23f6f76..8a5402d39 100644
--- a/src/common/gamecode/items.c
+++ b/src/common/gamecode/items.c
@@ -73,14 +73,14 @@ static int
 use_speedsail(struct unit * u, const struct item_type * itype, int amount, struct order * ord)
 {
   curse  *c;
-  variant effect;
+  double effect;
   ship * sh = u->ship;
   if (!sh) {
     cmistake(u, ord, 20, MSG_MOVE);
     return -1;
   }
 
-  effect.i = SPEEDSAIL_EFFECT;
+  effect = SPEEDSAIL_EFFECT;
   c = create_curse(u, &sh->attribs, ct_find("shipspeedup"), 20, INT_MAX, effect, 0);
   c_setflag(c, CURSE_NOAGE);
 
@@ -145,9 +145,7 @@ use_antimagiccrystal(unit * u, const struct item_type * itype, int amount, struc
     }
 
     if (force > 0) {
-      variant var ;
-      var.i = effect;
-      create_curse(u, &r->attribs, ct_find("antimagiczone"), force, duration, var, 0);
+      create_curse(u, &r->attribs, ct_find("antimagiczone"), force, duration, effect, 0);
     }
   }
   use_pooled(u, rt_crystal, GET_DEFAULT, amount);
@@ -208,7 +206,6 @@ use_bagpipeoffear(struct unit * u, const struct item_type * itype,
                   int amount, struct order * ord)
 {
   int money;
-  variant effect;
 
   if (get_curse(u->region->attribs, ct_find("depression"))) {
     cmistake(u, ord, 58, MSG_MAGIC);
@@ -219,9 +216,8 @@ use_bagpipeoffear(struct unit * u, const struct item_type * itype,
   change_money(u, money);
   rsetmoney(u->region, rmoney(u->region) - money);
 
-  effect.i = 0;
   create_curse(u, &u->region->attribs, ct_find("depression"),
-    20, BAGPIPEDURATION, effect, 0);
+    20, BAGPIPEDURATION, 0.0, 0);
 
   ADDMSG(&u->faction->msgs, msg_message("bagpipeoffear_faction",
     "unit region command money", u, u->region, ord, money));
diff --git a/src/common/gamecode/laws.c b/src/common/gamecode/laws.c
index 28d07db32..ec6adc4ef 100644
--- a/src/common/gamecode/laws.c
+++ b/src/common/gamecode/laws.c
@@ -3034,8 +3034,8 @@ age_building(building * b)
       if (c==NULL) {
         if (mage!=NULL) {
           int sk = effskill(mage, SK_MAGIC);
-          variant effect;
-          effect.i = 100;
+          double effect;
+          effect = 100;
           /* the mage reactivates the circle */
           c = create_curse(mage, &rt->attribs, ct_astralblock,
             (float)sk, sk/2, effect, 0);
@@ -3134,7 +3134,7 @@ ageing(void)
       if (is_cursed(u->attribs, C_OLDRACE, 0)){
         curse *c = get_curse(u->attribs, ct_find("oldrace"));
         if (c->duration == 1 && !(c_flags(c) & CURSE_NOAGE)) {
-          u->race = new_race[curse_geteffect(c)];
+          u->race = new_race[curse_geteffect_int(c)];
           u->irace = NULL;
         }
       }
@@ -3444,7 +3444,7 @@ monthly_healing(void)
 
   for (r = regions; r; r = r->next) {
     unit *u;
-    int healingcurse = 0;
+    double healingcurse = 0;
 
     if (heal_ct!=NULL) {
       /* bonus zurücksetzen */
diff --git a/src/common/gamecode/randenc.c b/src/common/gamecode/randenc.c
index 143c8a3dd..9d20fd002 100644
--- a/src/common/gamecode/randenc.c
+++ b/src/common/gamecode/randenc.c
@@ -1038,10 +1038,10 @@ orc_growth(void)
         int n;
         int increase = 0;
         int num  = get_cursedmen(u, c);
-        int prob = curse_geteffect(c);
+        double prob = curse_geteffect(c);
 
         for (n = (num - get_item(u, I_CHASTITY_BELT)); n > 0; n--) {
-          if (rng_int() % 100 < prob) {
+          if (chance(prob)) {
             ++increase;
           }
         }
diff --git a/src/common/items/artrewards.c b/src/common/items/artrewards.c
index 276e942ac..e73f99933 100644
--- a/src/common/items/artrewards.c
+++ b/src/common/items/artrewards.c
@@ -67,11 +67,9 @@ use_hornofdancing(struct unit * u, const struct item_type * itype,
     if(distance(u->region, r) < HORNRANGE) {
       if(a_find(r->attribs, &at_peaceimmune) == NULL) {
         attrib *a;
-        variant effect;
 
-        effect.i = 1;
         create_curse(u, &r->attribs, ct_find("peacezone"),
-          20, HORNDURATION, effect, 0);
+          20, HORNDURATION, 1.0, 0);
 
         a = a_add(&r->attribs, a_new(&at_peaceimmune));
         a->data.i = HORNIMMUNITY;
@@ -107,7 +105,6 @@ useonother_trappedairelemental(struct unit * u, int shipId,
 {
   curse  *c;
   ship   *sh;
-  variant effect;
 
   if (shipId <= 0) {
     cmistake(u, ord, 20, MSG_MOVE);
@@ -120,8 +117,7 @@ useonother_trappedairelemental(struct unit * u, int shipId,
     return -1;
   }
 
-  effect.i = SPEEDUP;
-  c = create_curse(u, &sh->attribs, ct_find("shipspeedup"), 20, INT_MAX, effect, 0);
+  c = create_curse(u, &sh->attribs, ct_find("shipspeedup"), 20, INT_MAX, SPEEDUP, 0);
   c_setflag(c, CURSE_NOAGE);
 
   ADDMSG(&u->faction->msgs, msg_message("trappedairelemental_success",
diff --git a/src/common/kernel/battle.c b/src/common/kernel/battle.c
index f196968b6..7baf11f38 100644
--- a/src/common/kernel/battle.c
+++ b/src/common/kernel/battle.c
@@ -1928,7 +1928,7 @@ skilldiff(troop at, troop dt, int dist)
       curse * c = get_curse(df->building->attribs, strongwall_ct);
       if (curse_active(c)) {
         /* wirkt auf alle Gebäude */
-        skdiff -= curse_geteffect(c);
+        skdiff -= curse_geteffect_int(c);
         is_protected = 2;
       }
     }
@@ -3275,7 +3275,7 @@ make_fighter(battle * b, unit * u, side * s1, boolean attack)
       curse *c = get_curse(u->attribs, speed_ct);
       if (c) {
         speeded = get_cursedmen(u, c);
-        speed   = curse_geteffect(c);
+        speed   = curse_geteffect_int(c);
       }
     }
   }
diff --git a/src/common/kernel/curse.c b/src/common/kernel/curse.c
index a09cc5d18..ecca96adf 100644
--- a/src/common/kernel/curse.c
+++ b/src/common/kernel/curse.c
@@ -206,7 +206,11 @@ curse_read(attrib * a, struct storage * store)
   } else {
     ur = read_reference(&c->magician, store, read_unit_reference, resolve_unit);
   }
-  c->effect.i = store->r_int(store);
+  if (store->version<CURSEFLOAT_VERSION) {
+    c->effect = (double)store->r_int(store);
+  } else {
+    c->effect = store->r_flt(store);
+  }
   c->type = ct_find(cursename);
   if (c->type==NULL) {
     int result = read_ccompat(cursename, store);
@@ -257,7 +261,7 @@ curse_write(const attrib * a, struct storage * store)
   store->w_int(store, c->duration);
   store->w_flt(store, (float)c->vigour);
   write_unit_reference(mage, store);
-  store->w_int(store, c->effect.i);
+  store->w_flt(store, (float)c->effect);
 
   if (c->type->write) c->type->write(store, c);
   else if (c->type->typ == CURSETYP_UNIT) {
@@ -435,12 +439,20 @@ curse_changevigour(attrib **ap, curse *c, double vigour)
 
 /* ------------------------------------------------------------- */
 
-int
+double
 curse_geteffect(const curse *c)
 {
   if (c==NULL) return 0;
   if (c_flags(c) & CURSE_ISNEW) return 0;
-  return c->effect.i;
+  return c->effect;
+}
+
+int
+curse_geteffect_int(const curse *c)
+{
+  double effect = curse_geteffect(c);
+  assert(effect-(int)effect == 0);
+  return (int)effect;
 }
 
 /* ------------------------------------------------------------- */
@@ -491,7 +503,7 @@ set_cursedmen(curse *c, int cursedmen)
  */
 static curse *
 make_curse(unit *mage, attrib **ap, const curse_type *ct, double vigour,
-    int duration, variant effect, int men)
+    int duration, double effect, int men)
 {
   curse *c;
   attrib * a;
@@ -532,7 +544,7 @@ make_curse(unit *mage, attrib **ap, const curse_type *ct, double vigour,
  */
 curse *
 create_curse(unit *magician, attrib **ap, const curse_type *ct, double vigour,
-    int duration, variant effect, int men)
+    int duration, double effect, int men)
 {
   curse *c;
 
@@ -555,10 +567,10 @@ create_curse(unit *magician, attrib **ap, const curse_type *ct, double vigour,
       c->duration += duration;
     }
     if(ct->mergeflags & M_SUMEFFECT){
-      c->effect.i += effect.i;
+      c->effect += effect;
     }
     if(ct->mergeflags & M_MAXEFFECT){
-      c->effect.i = MAX(c->effect.i, effect.i);
+      c->effect = MAX(c->effect, effect);
     }
     if(ct->mergeflags & M_VIGOUR){
       c->vigour = MAX(vigour, c->vigour);
diff --git a/src/common/kernel/curse.h b/src/common/kernel/curse.h
index 79c7af33e..ee3a18fa8 100644
--- a/src/common/kernel/curse.h
+++ b/src/common/kernel/curse.h
@@ -191,7 +191,7 @@ typedef struct curse {
   int duration;      /* Dauer der Verzauberung. Wird jede Runde vermindert */
   double vigour;        /* Stärke der Verzauberung, Widerstand gegen Antimagie */
   struct unit *magician;    /* Pointer auf den Magier, der den Spruch gewirkt hat */
-  variant effect;
+  double effect;
   variant data;        /* pointer auf spezielle curse-unterstructs*/
 } curse;
 
@@ -240,7 +240,7 @@ extern int curse_read(struct attrib * a, struct storage * store);
 */
 
 curse * create_curse(struct unit *magician, struct attrib**ap, const curse_type * ctype,
-    double vigour, int duration, variant ceffect, int men);
+    double vigour, int duration, double ceffect, int men);
   /* Verzweigt automatisch zum passenden struct-typ. Sollte es schon
    * einen Zauber dieses Typs geben, so wird der neue dazuaddiert. Die
    * Zahl der verzauberten Personen sollte beim Aufruf der Funktion
@@ -257,7 +257,8 @@ extern void remove_curse(struct attrib **ap, const struct curse * c);
   /* löscht einen konkreten Spruch auf einem Objekt.
    */
 
-extern int curse_geteffect(const struct curse * c);
+extern int curse_geteffect_int(const struct curse * c);
+extern double curse_geteffect(const struct curse * c);
   /* gibt die Auswirkungen der Verzauberungen zurück. zB bei
    * Skillmodifiziernden Verzauberungen ist hier der Modifizierer
    * gespeichert. Wird automatisch beim Anlegen eines neuen curse
diff --git a/src/common/kernel/eressea.c b/src/common/kernel/eressea.c
index 16bc1006a..6b9c7b383 100644
--- a/src/common/kernel/eressea.c
+++ b/src/common/kernel/eressea.c
@@ -636,7 +636,7 @@ ShipSpeedBonus(const unit * u)
 int
 shipspeed(const ship * sh, const unit * u)
 {
-  int k = sh->type->range;
+  double k = sh->type->range;
   static const curse_type * stormwind_ct, * nodrift_ct;
   static boolean init;
   attrib *a;
@@ -686,7 +686,7 @@ shipspeed(const ship * sh, const unit * u)
   if (sh->damage) k = (k * (sh->size * DAMAGE_SCALE - sh->damage) + sh->size * DAMAGE_SCALE- 1) / (sh->size*DAMAGE_SCALE);
 #endif
 
-  return k;
+  return (int)k;
 }
 
 #define FMAXHASH 2039
@@ -2654,7 +2654,7 @@ default_wage(const region *r, const faction * f, const race * rc)
   building *b = largestbuilding(r, &is_castle, false);
   int      esize = 0;
   curse * c;
-  int      wage;
+  double wage;
   attrib   *a;
   const building_type *artsculpture_type = bt_find("artsculpture");
   static const curse_type * drought_ct, * blessedharvest_ct;
@@ -2717,7 +2717,7 @@ default_wage(const region *r, const faction * f, const race * rc)
   a = a_find(r->attribs, &at_reduceproduction);
   if (a) wage = (wage * a->data.sa[0])/100;
 
-  return wage;
+  return (int)wage;
 }
 
 static int
@@ -3048,7 +3048,7 @@ default_order(const struct locale * lang)
 int
 entertainmoney(const region *r)
 {
-  int n;
+  double n;
 
   if (is_cursed(r->attribs, C_DEPRESSION, 0)) {
     return 0;
@@ -3060,7 +3060,7 @@ entertainmoney(const region *r)
     n *= get_curseeffect(r->attribs, C_GENEROUS, 0);
   }
 
-  return n;
+  return (int)n;
 }
 
 int rule_give(void)
diff --git a/src/common/kernel/item.c b/src/common/kernel/item.c
index 31e68f7c4..cc987510b 100644
--- a/src/common/kernel/item.c
+++ b/src/common/kernel/item.c
@@ -693,9 +693,9 @@ use_tacticcrystal(unit * u, const struct item_type * itype, int amount, struct o
                       Fall egal, da der curse für den Kampf gelten soll,
                       der vor den Antimagiezaubern passiert */
     curse * c;
-    variant effect;
+    double effect;
 
-    effect.i = rng_int()%6 - 1;
+    effect = rng_int()%6 - 1;
     c = create_curse(u, &u->attribs, ct_find("skillmod"), power,
       duration, effect, u->number);
     c->data.i = SK_TACTICS;
diff --git a/src/common/kernel/magic.c b/src/common/kernel/magic.c
index 551238095..1c0f93b09 100644
--- a/src/common/kernel/magic.c
+++ b/src/common/kernel/magic.c
@@ -772,8 +772,8 @@ use_item_aura(const region * r, const unit * u)
 int
 max_spellpoints(const region * r, const unit * u)
 {
-  int sk, n;
-  double msp;
+  int sk;
+  double n, msp;
   double potenz = 2.1;
   double divisor = 1.2;
 
@@ -1387,7 +1387,7 @@ do_fumble(castorder *co)
   const spell *sp = co->sp;
   int level = co->level;
   int duration;
-  variant effect;
+  double effect;
 
   ADDMSG(&u->faction->msgs, msg_message("patzer", "unit region spell",
     u, r, sp));
@@ -1429,7 +1429,7 @@ do_fumble(castorder *co)
   case 2:
     /* temporärer Stufenverlust */
     duration = MAX(rng_int()%level/2, 2);
-    effect.i = -(level/2);
+    effect = -0.5*level;
     c = create_curse(u, &u->attribs, ct_find("skillmod"), (float)level, duration,
       effect, 1);
     c->data.i = SK_MAGIC;
@@ -1517,7 +1517,7 @@ regeneration_magiepunkte(void)
   int aura, auramax;
   double reg_aura;
   int regen;
-  int n;
+  double mod;
 
   for (r = regions; r; r = r->next) {
     for (u = r->units; u; u = u->next) {
@@ -1534,9 +1534,9 @@ regeneration_magiepunkte(void)
           if (btype) reg_aura *= btype->auraregen;
 
           /* Bonus/Malus durch Zauber */
-          n = get_curseeffect(u->attribs, C_AURA, 0);
-          if (n>0) {
-            reg_aura = (reg_aura*n)/100;
+          mod = get_curseeffect(u->attribs, C_AURA, 0);
+          if (mod>0) {
+            reg_aura = (reg_aura*mod)/100.0;
           }
 
           /* Einfluss von Artefakten */
diff --git a/src/common/kernel/version.h b/src/common/kernel/version.h
index 6fe9e1522..5198f4e03 100644
--- a/src/common/kernel/version.h
+++ b/src/common/kernel/version.h
@@ -62,6 +62,7 @@
 #define UIDHASH_VERSION 332 /* borders use the region.uid to store */
 #define REGIONOWNER_VERSION 333 /* regions have owners and morale */
 #define ALLIANCELEADER_VERSION 333 /* alliances have a leader */
+#define CURSEFLOAT_VERSION 334 /* all curse-effects are float */
 
 #define MIN_VERSION CURSETYPE_VERSION /* minimal datafile we support */
-#define RELEASE_VERSION ALLIANCELEADER_VERSION /* current datafile */
+#define RELEASE_VERSION CURSEFLOAT_VERSION /* current datafile */
diff --git a/src/common/spells/alp.c b/src/common/spells/alp.c
index 7f74c1c7b..efb8ec86f 100644
--- a/src/common/spells/alp.c
+++ b/src/common/spells/alp.c
@@ -152,7 +152,7 @@ alp_findet_opfer(unit *alp, region *r)
   alp_data * ad = (alp_data*)a->data.v;
   unit *mage = ad->mage;
   unit *opfer = ad->target;
-  variant effect;
+  double effect;
   message * msg;
 
   assert(opfer);
@@ -172,7 +172,7 @@ alp_findet_opfer(unit *alp, region *r)
   a_removeall(&alp->attribs, &at_eventhandler);
 
   /* Alp umwandeln in Curse */
-  effect.i = -2;
+  effect = -2;
   c = create_curse(mage, &opfer->attribs, ct_find("worse"), 2, 2, effect, opfer->number);
   /* solange es noch keine spezielle alp-Antimagie gibt, reagiert der
   * auch auf normale */
diff --git a/src/common/spells/combatspells.c b/src/common/spells/combatspells.c
index 4091e4ffc..61554381a 100644
--- a/src/common/spells/combatspells.c
+++ b/src/common/spells/combatspells.c
@@ -841,7 +841,7 @@ sp_strong_wall(fighter * fi, int level, double power, spell * sp)
   battle *b = fi->side->battle;
   unit *mage = fi->unit;
   building *burg;
-  variant effect;
+  double effect;
   static boolean init = false;
   message * msg;
   static const curse_type * strongwall_ct;
@@ -854,9 +854,7 @@ sp_strong_wall(fighter * fi, int level, double power, spell * sp)
   }
   burg = mage->building;
 
-  effect.i = (int)(power/4);
-  if (chance(power-effect.i)) ++effect.i;
-
+  effect = power*0.25;
   create_curse(mage, &burg->attribs, strongwall_ct, power, 1, effect, 0);
 
   msg = msg_message("sp_strongwalls_effect", "mage building", mage, mage->building);
diff --git a/src/common/spells/spells.c b/src/common/spells/spells.c
index bd9ae1f09..3a4197146 100644
--- a/src/common/spells/spells.c
+++ b/src/common/spells/spells.c
@@ -96,7 +96,7 @@
 #include <attributes/hate.h>
 /* ----------------------------------------------------------------------- */
 
-static variant zero_effect = { 0 };
+static double zero_effect = 0.0;
 
 attrib_type at_unitdissolve = {
   "unitdissolve", NULL, NULL, NULL, a_writechars, a_readchars
@@ -996,7 +996,7 @@ sp_maelstrom(castorder *co)
   int cast_level = co->level;
   curse * c;
   double power = co->force;
-  variant effect;
+  double effect = co->force;
   int duration = (int)power+1;
 
   if (!fval(r->terrain, SEA_REGION)) {
@@ -1008,7 +1008,6 @@ sp_maelstrom(castorder *co)
   /* Attribut auf Region.
    * Existiert schon ein curse, so wird dieser verstärkt
    * (Max(Dauer), Max(Stärke))*/
-  effect.i = (int)power;
   c = create_curse(mage, &r->attribs, ct_find("maelstrom"), power, duration, effect, 0);
 
   /* melden, 1x pro Partei */
@@ -1087,25 +1086,25 @@ sp_blessedharvest(castorder *co)
   unit *mage = co->magician.u;
   int cast_level = co->level;
   double power = co->force;
-  variant effect;
+  double effect;
   int rule = rule_blessed_harvest();
   /* Attribut auf Region.
    * Existiert schon ein curse, so wird dieser verstärkt
    * (Max(Dauer), Max(Stärke))*/
   if (rule==HARVEST_WORK) {
     int duration = (int)power+1;
-    effect.i = 1;
+    effect = 1;
     create_curse(mage, &r->attribs, ct_find("blessedharvest"), power, duration, effect, 0);
   } else if (rule==HARVEST_TAXES) {
     int duration = (int)(power*2);
     if (co->sp->id!=SPL_BLESSEDHARVEST) {
-      effect.i = (int)(100 * power);
+      effect = (int)(100 * power);
       create_curse(mage, &r->attribs, ct_find("blessedharvest"), power, duration, effect, 0);
     } else {
       int d;
       region * rn[MAXDIRECTIONS];
       get_neighbours(r, rn);
-      effect.i = (int)(50 * power);
+      effect = (int)(50 * power);
       for (d=0;d!=MAXDIRECTIONS;++d) {
         region * rx = rn[d];
         if (rx && rx->land) {
@@ -1387,7 +1386,7 @@ sp_kaelteschutz(castorder *co)
   double force = co->force;
   int duration = MAX(cast_level, (int)force) + 1;
   spellparameter *pa = co->par;
-  variant effect;
+  double effect;
 
   force*=10;  /* 10 Personen pro Force-Punkt */
 
@@ -1408,7 +1407,7 @@ sp_kaelteschutz(castorder *co)
       men = u->number;
     }
 
-    effect.i = 1;
+    effect = 1;
     create_curse(mage, &u->attribs, ct_find("insectfur"), cast_level,
         duration, effect, men);
 
@@ -1447,7 +1446,7 @@ sp_sparkle(castorder *co)
   int cast_level = co->level;
   spellparameter *pa = co->par;
   int duration = cast_level+1;
-  variant effect;
+  double effect;
 
   /* wenn kein Ziel gefunden, Zauber abbrechen */
   if (pa->param[0]->flag == TARGET_NOTFOUND) return 0;
@@ -1457,7 +1456,7 @@ sp_sparkle(castorder *co)
   if (pa->param[0]->flag == TARGET_RESISTS) return cast_level;
 
   u = pa->param[0]->data.u;
-  effect.i = rng_int();
+  effect = rng_int() % 0xffffff;
   create_curse(mage, &u->attribs, ct_find("sparkle"), cast_level,
       duration, effect, u->number);
 
@@ -1632,7 +1631,7 @@ sp_great_drought(castorder *co)
   int cast_level = co->level;
   double force = co->force;
   int duration = 2;
-  variant effect;
+  double effect;
 
   if (fval(r->terrain, SEA_REGION) ) {
     cmistake(mage, co->order, 189, MSG_MAGIC);
@@ -1648,7 +1647,7 @@ sp_great_drought(castorder *co)
   rsethorses(r, rhorses(r)/2);
 
   /* Arbeitslohn = 1/4 */
-  effect.i = 4;
+  effect = 4.0; /* curses: higher is stronger */
   create_curse(mage, &r->attribs, ct_find("drought"), force, duration, effect, 0);
 
   /* terraforming */
@@ -2031,7 +2030,7 @@ sp_homestone(castorder *co)
   unit *mage = co->magician.u;
   int cast_level = co->level;
   double force = co->force;
-  variant effect;
+  double effect;
   message * msg;
   if (!mage->building || mage->building->type != bt_find("castle")) {
     cmistake(mage, co->order, 197, MSG_MAGIC);
@@ -2048,7 +2047,7 @@ sp_homestone(castorder *co)
   c_setflag(c, CURSE_NOAGE|CURSE_ONLYONE);
 
   /* Magieresistenz der Burg erhöht sich um 50% */
-  effect.i = 50;
+  effect = 50;
   c = create_curse(mage,  &mage->building->attribs,
     ct_find("magicresistance"), force*force, 1, effect, 0);
   c_setflag(c, CURSE_NOAGE);
@@ -2115,14 +2114,14 @@ sp_drought(castorder *co)
     c->vigour = MAX(c->vigour, power);
     c->duration = MAX(c->duration, (int)power);
   } else {
-    variant effect;
+    double effect;
     /* Baeume und Pferde sterben */
     rsettrees(r, 2, rtrees(r,2)/2);
     rsettrees(r, 1, rtrees(r,1)/2);
     rsettrees(r, 0, rtrees(r,0)/2);
     rsethorses(r, rhorses(r)/2);
 
-    effect.i = 4;
+    effect = 4.0;
     create_curse(mage, &r->attribs, ct_find("drought"), power, duration, effect, 0);
   }
   return cast_level;
@@ -2486,7 +2485,7 @@ sp_fumblecurse(castorder *co)
   unit *mage = co->magician.u;
   int cast_level = co->level;
   double force = co->force;
-  variant effect;
+  double effect;
   curse * c;
   spellparameter *pa = co->par;
 
@@ -2499,7 +2498,7 @@ sp_fumblecurse(castorder *co)
   sx = cast_level - effskill(target, SK_MAGIC);
   duration = MAX(sx, rx) + 1;
 
-  effect.i = (int)(force/2);
+  effect = force*0.5;
   c = create_curse(mage, &target->attribs, ct_find("fumble"),
     force, duration, effect, 0);
   if (c == NULL) {
@@ -2520,10 +2519,10 @@ patzer_fumblecurse(castorder *co)
   int cast_level = co->level;
   double force = co->force;
   int duration = (cast_level/2)+1;
-  variant effect;
+  double effect;
   curse * c;
 
-  effect.i = (int)(force/2);
+  effect = force*0.5;
   c = create_curse(mage, &mage->attribs, ct_find("fumble"), force,
         duration, effect, 0);
   if (c!=NULL) {
@@ -3135,7 +3134,7 @@ dc_age(struct curse * c)
   up = &r->units;
   if (curse_active(c)) while (*up!=NULL) {
     unit * u = *up;
-    double damage = c->effect.f * u->number;
+    double damage = c->effect * u->number;
 
     freset(u->faction, FFL_SELECT);
     if (u->number<=0 || target_resists_magic(mage, u, TYP_UNIT, 0)) {
@@ -3160,10 +3159,10 @@ static struct curse_type ct_deathcloud = {
 static curse *
 mk_deathcloud(unit * mage, region * r, double force, int duration)
 {
-  variant effect;
+  double effect;
   curse * c;
 
-  effect.f = (float)force/2;
+  effect = force * 0.5;
   c = create_curse(mage, &r->attribs, &ct_deathcloud, force, duration, effect, 0);
   c->data.v = r;
   return c;
@@ -3191,10 +3190,10 @@ dc_read_compat(struct attrib * a, storage * store)
   r = findregion(rx, ry);
 
   if (r!=NULL) {
-    variant effect;
+    double effect;
     curse * c;
 
-    effect.f = (float)strength;
+    effect = strength;
     c = create_curse(u, &r->attribs, &ct_deathcloud, strength * 2, duration, effect, 0);
     c->data.v = r;
     if (u==NULL) {
@@ -3469,7 +3468,7 @@ sp_magicboost(castorder *co)
   unit *mage = co->magician.u;
   int cast_level = co->level;
   double power = co->force;
-  variant effect;
+  double effect;
   trigger * tsummon;
   static const curse_type * ct_auraboost;
   static const curse_type * ct_magicboost;
@@ -3486,11 +3485,11 @@ sp_magicboost(castorder *co)
     return 0;
   }
 
-  effect.i = 6;
+  effect = 6;
   c = create_curse(mage, &mage->attribs, ct_magicboost, power, 10, effect, 1);
 
   /* one aura boost with 200% aura now: */
-  effect.i = 200;
+  effect = 200;
   c = create_curse(mage, &mage->attribs, ct_auraboost, power, 4, effect, 1);
 
   /* and one aura boost with 50% aura in 5 weeks: */
@@ -3912,16 +3911,14 @@ sp_charmingsong(castorder *co)
 static int
 sp_song_resistmagic(castorder *co)
 {
-  variant mr_bonus;
   region *r = co->rt;
   unit *mage = co->magician.u;
   int cast_level = co->level;
   double force = co->force;
   int duration = (int)force+1;
 
-  mr_bonus.i = 15;
   create_curse(mage, &r->attribs, ct_find("goodmagicresistancezone"),
-      force, duration, mr_bonus, 0);
+      force, duration, 15, 0);
 
   /* Erfolg melden */
   ADDMSG(&mage->faction->msgs, msg_message(
@@ -3944,16 +3941,14 @@ sp_song_resistmagic(castorder *co)
 static int
 sp_song_susceptmagic(castorder *co)
 {
-  variant mr_malus;
   region *r = co->rt;
   unit *mage = co->magician.u;
   int cast_level = co->level;
   double force = co->force;
   int duration = (int)force+1;
 
-  mr_malus.i = 15;
   create_curse(mage, &r->attribs, ct_find("badmagicresistancezone"),
-      force, duration, mr_malus, 0);
+      force, duration, 15, 0);
 
   ADDMSG(&mage->faction->msgs, msg_message(
         "regionmagic_effect", "unit region command", mage,
@@ -4030,7 +4025,7 @@ sp_raisepeasantmob(castorder *co)
   unit *u;
   attrib *a;
   int n;
-  variant anteil;
+  int anteil;
   region *r = co->rt;
   unit *mage = co->magician.u;
   int cast_level = co->level;
@@ -4039,9 +4034,9 @@ sp_raisepeasantmob(castorder *co)
   faction * monsters = get_monsters();
   message * msg;
 
-  anteil.i = 6 + (rng_int()%4);
+  anteil = 6 + (rng_int()%4);
 
-  n = rpeasants(r) * anteil.i / 10;
+  n = rpeasants(r) * anteil / 10;
   n = MAX(0, n);
   n = MIN(n, rpeasants(r));
 
@@ -4061,7 +4056,7 @@ sp_raisepeasantmob(castorder *co)
   a->data.ca[1] = 15; /* 15% */
   a_add(&u->attribs, a);
 
-  create_curse(mage, &r->attribs, ct_find("riotzone"), cast_level, duration, anteil, 0);
+  create_curse(mage, &r->attribs, ct_find("riotzone"), cast_level, duration, (double)anteil, 0);
 
   msg = msg_message("sp_raisepeasantmob_effect", "mage region", mage, r);
   report_spell(mage, r, msg);
@@ -4204,7 +4199,7 @@ sp_generous(castorder *co)
   int cast_level = co->level;
   double force = co->force;
   int duration = (int)force+1;
-  variant effect;
+  double effect;
   message * msg[2] = { NULL, NULL };
 
   if (is_cursed(r->attribs, C_DEPRESSION, 0)) {
@@ -4212,7 +4207,7 @@ sp_generous(castorder *co)
     return 0;
   }
 
-  effect.i = 2;
+  effect = 2;
   create_curse(mage,&r->attribs, ct_find("generous"), force, duration, effect, 0);
 
   for (u = r->units; u; u = u->next) freset(u->faction, FFL_SELECT);
@@ -4491,7 +4486,7 @@ sp_calm_monster(castorder *co)
   spellparameter *pa = co->par;
   int cast_level = co->level;
   double force = co->force;
-  variant effect;
+  double effect;
   message * msg;
 
   /* wenn kein Ziel gefunden, Zauber abbrechen */
@@ -4505,7 +4500,7 @@ sp_calm_monster(castorder *co)
     return 0;
   }
 
-  effect.i = mage->faction->subscription;
+  effect = mage->faction->subscription;
   c = create_curse(mage, &target->attribs, ct_find("calmmonster"), force,
     (int)force, effect, 0);
   if (c==NULL) {
@@ -4992,7 +4987,7 @@ sp_baddreams(castorder *co)
   double power = co->force;
   region *r = co->rt;
   curse * c;
-  variant effect;
+  double effect;
 
   /* wirkt erst in der Folgerunde, soll mindestens eine Runde wirken,
    * also duration+2 */
@@ -5000,7 +4995,7 @@ sp_baddreams(castorder *co)
   duration = 2 + rng_int()%duration;
 
   /* Nichts machen als ein entsprechendes Attribut in die Region legen. */
-  effect.i = -1;
+  effect = -1;
   c = create_curse(mage, &r->attribs, ct_find("gbdream"), power, duration, effect, 0);
 
   /* Erfolg melden*/
@@ -5032,13 +5027,13 @@ sp_gooddreams(castorder *co)
   unit *mage = co->magician.u;
   int cast_level = co->level;
   double power = co->force;
-  variant effect;
+  double effect;
 
   /* wirkt erst in der Folgerunde, soll mindestens eine Runde wirken,
    * also duration+2 */
   duration = (int)MAX(1, power/2); /* Stufe 1 macht sonst mist */
   duration = 2 + rng_int()%duration;
-  effect.i = 1;
+  effect = 1;
   c = create_curse(mage, &r->attribs, ct_find("gbdream"), power, duration, effect, 0);
 
   /* Erfolg melden*/
@@ -5153,7 +5148,7 @@ sp_sweetdreams(castorder *co)
   for (n = 0; n < pa->length; n++) {
     curse * c;
     unit *u;
-    variant effect;
+    double effect;
     message * msg;
     /* sollte nie negativ werden */
     if (opfer < 1) break;
@@ -5173,7 +5168,7 @@ sp_sweetdreams(castorder *co)
     opfer -= men;
 
     /* Nichts machen als ein entsprechendes Attribut an die Einheit legen. */
-    effect.i = 5;
+    effect = 0.05;
     c = create_curse(mage,&u->attribs, ct_find("orcish"), power, duration, effect, men);
 
     msg = msg_message("sp_sweetdreams_effect", "mage unit region", mage, u, r);
@@ -5195,10 +5190,10 @@ sp_disturbingdreams(castorder *co)
   int cast_level = co->level;
   double power = co->force;
   int duration = 1 + (int)(power/6);
-  variant effect;
+  double effect;
   curse * c;
 
-  effect.i = 10;
+  effect = 10;
   c = create_curse(mage, &r->attribs, ct_find("badlearn"), power, duration, effect, 0);
 
   ADDMSG(&mage->faction->msgs, msg_message("sp_disturbingdreams_effect", "mage region", mage, r));
@@ -5317,7 +5312,6 @@ sp_resist_magic_bonus(castorder *co)
 {
   unit *u;
   int n, m;
-  variant resistbonus;
   int duration = 6;
   unit *mage = co->magician.u;
   int cast_level = co->level;
@@ -5349,9 +5343,8 @@ sp_resist_magic_bonus(castorder *co)
     m = MIN(u->number,victims);
     victims -= m;
 
-    resistbonus.i = 20;
     create_curse(mage, &u->attribs, ct_find("magicresistance"),
-      power, duration, resistbonus, m);
+      power, duration, 20, m);
 
     msg = msg_message("magicresistance_effect", "unit", u);
     add_message(&u->faction->msgs, msg);
@@ -5982,7 +5975,7 @@ sp_disruptastral(castorder *co)
 
   for (rl2=rl; rl2!=NULL; rl2=rl2->next) {
     attrib *a;
-    variant effect;
+    double effect;
     region * r2 = rl2->data;
     spec_direction *sd;
     int inhab_regions = 0;
@@ -6034,7 +6027,7 @@ sp_disruptastral(castorder *co)
     }
 
     /* Kontakt unterbinden */
-    effect.i = 100;
+    effect = 100;
     create_curse(mage, &rl2->data->attribs, ct_find("astralblock"),
       power, duration, effect, 0);
   }
@@ -6422,7 +6415,7 @@ int
 sp_antimagiczone(castorder *co)
 {
   double power;
-  variant effect;
+  double effect;
   region *r = co->rt;
   unit *mage = co->magician.u;
   int cast_level = co->level;
@@ -6435,7 +6428,7 @@ sp_antimagiczone(castorder *co)
   power = force * 10;
 
   /* Reduziert die Stärke jedes Spruchs um effect */
-  effect.i = cast_level;
+  effect = cast_level;
 
   create_curse(mage, &r->attribs, ct_find("antimagiczone"), power, duration,
       effect, 0);
@@ -6487,10 +6480,10 @@ sp_magicrunes(castorder *co)
   int cast_level = co->level;
   double force = co->force;
   spellparameter *pa = co->par;
-  variant effect;
+  double effect;
 
   duration = 3 + rng_int()%cast_level;
-  effect.i = 20;
+  effect = 20;
 
   switch(pa->param[0]->typ) {
     case SPP_BUILDING:
@@ -6553,7 +6546,7 @@ sp_speed2(castorder *co)
   dur = MAX(1, cast_level/2);
 
   for (n = 0; n < pa->length; n++) {
-    variant effect;
+    double effect;
     /* sollte nie negativ werden */
     if (maxmen < 1)
       break;
@@ -6565,7 +6558,7 @@ sp_speed2(castorder *co)
     u = pa->param[n]->data.u;
 
     men = MIN(maxmen,u->number);
-    effect.i = 2;
+    effect = 2;
     create_curse(mage, &u->attribs, ct_find("speed"), force, dur, effect, men);
     maxmen -= men;
     used += men;
diff --git a/src/common/spells/unitcurse.c b/src/common/spells/unitcurse.c
index 5fcc611be..fdeb61c6b 100644
--- a/src/common/spells/unitcurse.c
+++ b/src/common/spells/unitcurse.c
@@ -243,7 +243,7 @@ cinfo_sparkle(const void * obj, typ_t typ, const curse *c, int self)
   while (effects[end]!=NULL) ++end;
   if (end==begin) return NULL;
   else {
-    int index = begin + curse_geteffect(c) % (end-begin);
+    int index = begin + curse_geteffect_int(c) % (end-begin);
     return msg_message(mkname("curseinfo", effects[index]), "unit id", u, c->no);
   }
 }
@@ -327,9 +327,9 @@ cinfo_skillmod(const void * obj, typ_t typ, const curse *c, int self)
   if (self != 0) {
     unit *u = (unit *)obj;
     int sk = c->data.i;
-    if (c->effect.i>0) {
+    if (c->effect>0) {
       return msg_message("curseinfo::skill_1", "unit skill id", u, sk, c->no);
-    } else if (c->effect.i<0) {
+    } else if (c->effect<0) {
       return msg_message("curseinfo::skill_2", "unit skill id", u, sk, c->no);
     }
   }
diff --git a/src/common/triggers/createcurse.c b/src/common/triggers/createcurse.c
index 12958e871..9f0648428 100644
--- a/src/common/triggers/createcurse.c
+++ b/src/common/triggers/createcurse.c
@@ -46,7 +46,7 @@ typedef struct createcurse_data {
 	const curse_type * type;
 	double vigour;
 	int duration;
-	int effect;
+	double effect;
 	int men;
 } createcurse_data;
 
@@ -70,10 +70,8 @@ createcurse_handle(trigger * t, void * data)
   */
   createcurse_data * td = (createcurse_data*)t->data.v;
   if (td->mage && td->target && td->mage->number && td->target->number) {
-    variant var;
-    var.i = td->effect;
     create_curse(td->mage, &td->target->attribs,
-      td->type, td->vigour, td->duration, var, td->men);
+      td->type, td->vigour, td->duration, td->effect, td->men);
   } else {
     log_error(("could not perform createcurse::handle()\n"));
   }
@@ -90,7 +88,7 @@ createcurse_write(const trigger * t, struct storage * store)
   store->w_tok(store, td->type->cname);
   store->w_flt(store, (float)td->vigour);
   store->w_int(store, td->duration);
-  store->w_int(store, td->effect);
+  store->w_flt(store, (float)td->effect);
   store->w_int(store, td->men);
 }
 
@@ -118,7 +116,11 @@ createcurse_read(trigger * t, struct storage * store)
     td->type = ct_find(zText);
     td->vigour = store->r_flt(store);
     td->duration = store->r_int(store);
-    td->effect = store->r_int(store);
+    if (store->version<CURSEFLOAT_VERSION) {
+      td->effect = (double)store->r_int(store);
+    } else {
+      td->effect = store->r_flt(store);
+    }
     td->men = store->r_int(store);
   }
   return AT_READ_OK;
@@ -136,7 +138,7 @@ trigger_type tt_createcurse = {
 trigger *
 trigger_createcurse(struct unit * mage, struct unit * target,
 					const curse_type * ct, double vigour, int duration,
-					int effect, int men)
+					double effect, int men)
 {
 	trigger * t = t_new(&tt_createcurse);
 	createcurse_data * td = (createcurse_data*)t->data.v;
diff --git a/src/common/triggers/createcurse.h b/src/common/triggers/createcurse.h
index 86f31dfa8..e83d4cf33 100644
--- a/src/common/triggers/createcurse.h
+++ b/src/common/triggers/createcurse.h
@@ -28,7 +28,7 @@ struct unit;
 
 extern struct trigger_type tt_createcurse;
 
-extern struct trigger * trigger_createcurse(struct unit * mage, struct unit * target, const struct curse_type * ct, double vigour, int duration, int effect, int men);
+extern struct trigger * trigger_createcurse(struct unit * mage, struct unit * target, const struct curse_type * ct, double vigour, int duration, double effect, int men);
 
 #ifdef __cplusplus
 }
diff --git a/src/eressea/korrektur.c b/src/eressea/korrektur.c
index 82265a20e..33f7c5e80 100644
--- a/src/eressea/korrektur.c
+++ b/src/eressea/korrektur.c
@@ -115,9 +115,8 @@ curse_emptiness(void)
         }
       }
       if (d!=MAXDIRECTIONS) {
-        variant effect;
+        double effect = 0.0;
         curse * c;
-        effect.i = 0;
         c = create_curse(NULL, &r->attribs, ct, 100, 100, effect, 0);
       }
       freset(r, RF_MARK);