diff --git a/res/core/de/strings.xml b/res/core/de/strings.xml
index e7b13a89c..090344483 100644
--- a/res/core/de/strings.xml
+++ b/res/core/de/strings.xml
@@ -7503,11 +7503,6 @@
 
   </namespace>
 
-  <string name="nr_reduced_production">
-    <text locale="de">Die Region ist verwüstet, der Boden karg.</text>
-    <text locale="en">The region is ravaged, the ground infertile.</text>
-  </string>
-
   <string name="par_unit">
     <text locale="de">Einheit-Nr</text>
     <text locale="en">unitid</text>
diff --git a/res/core/messages.xml b/res/core/messages.xml
index 3e16e8301..00f0107e9 100644
--- a/res/core/messages.xml
+++ b/res/core/messages.xml
@@ -1,5 +1,10 @@
 <?xml version="1.0" encoding="utf-8" ?>
 <messages>
+  <message name="reduced_production">
+    <text locale="de">Die Region ist verwüstet, der Boden karg.</text>
+    <text locale="en">The region is ravaged, the ground infertile.</text>
+  </message>
+
   <message name="force_leave_ship" section="events">
     <type>
       <arg name="unit" type="unit"/>
diff --git a/src/alchemy.c b/src/alchemy.c
index a1dd86c0a..3d37af6a7 100644
--- a/src/alchemy.c
+++ b/src/alchemy.c
@@ -238,9 +238,10 @@ static void free_potiondelay(attrib * a)
     free(a->data.v);
 }
 
-static int age_potiondelay(attrib * a)
+static int age_potiondelay(attrib * a, void *owner)
 {
     potiondelay *pd = (potiondelay *)a->data.v;
+    unused_arg(owner);
     pd->amount = do_potion(pd->u, pd->r, pd->ptype, pd->amount);
     return AT_AGE_REMOVE;
 }
diff --git a/src/attributes/hate.c b/src/attributes/hate.c
index dd228b132..84768944a 100644
--- a/src/attributes/hate.c
+++ b/src/attributes/hate.c
@@ -28,8 +28,9 @@ OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 
 #include <storage.h>
 
-static int verify_hate(attrib * a)
+static int verify_hate(attrib * a, void *owner)
 {
+    unused_arg(owner);
     if (a->data.v == NULL) {
         return 0;
     }
diff --git a/src/attributes/moved.c b/src/attributes/moved.c
index 781162ea2..b671646c1 100644
--- a/src/attributes/moved.c
+++ b/src/attributes/moved.c
@@ -24,8 +24,9 @@ OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 
 #include <storage.h>
 
-static int age_moved(attrib * a)
+static int age_moved(attrib * a, void *owner)
 {
+    unused_arg(owner);
     --a->data.i;
     return a->data.i > 0;
 }
diff --git a/src/attributes/movement.c b/src/attributes/movement.c
index beb3998f0..ca8b6fc2f 100644
--- a/src/attributes/movement.c
+++ b/src/attributes/movement.c
@@ -65,8 +65,9 @@ void set_movement(attrib ** alist, int type)
     a->data.i |= type;
 }
 
-static int age_speedup(attrib * a)
+static int age_speedup(attrib * a, void *owner)
 {
+    unused_arg(owner);
     if (a->data.sa[0] > 0) {
         assert(a->data.sa[0] - a->data.sa[1] >= SHRT_MIN);
         assert(a->data.sa[0] - a->data.sa[1] <= SHRT_MAX);
diff --git a/src/attributes/reduceproduction.c b/src/attributes/reduceproduction.c
index 4472a5288..58436bc8e 100644
--- a/src/attributes/reduceproduction.c
+++ b/src/attributes/reduceproduction.c
@@ -20,15 +20,26 @@ OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 #include <kernel/config.h>
 #include "reduceproduction.h"
 #include <kernel/save.h>
+#include <kernel/region.h>
+#include <kernel/messages.h>
+#include <util/message.h>
 #include <util/attrib.h>
+#include <assert.h>
 
-static int age_reduceproduction(attrib * a)
+static int age_reduceproduction(attrib * a, void *owner)
 {
+    region * r = (region *)owner;
     int reduce = 100 - (5 * --a->data.sa[1]);
-    if (reduce < 10)
+    assert(r);
+    if (reduce < 10) {
         reduce = 10;
+    }
     a->data.sa[0] = (short)reduce;
-    return (a->data.sa[1] > 0) ? AT_AGE_KEEP : AT_AGE_REMOVE;
+    if (a->data.sa[1] > 0) {
+        ADDMSG(&r->msgs, msg_message("reduced_production", ""));
+        return AT_AGE_KEEP;
+    }
+    return AT_AGE_REMOVE;
 }
 
 attrib_type at_reduceproduction = {
diff --git a/src/bind_tolua.c b/src/bind_tolua.c
index c6df54a10..9a5b8e184 100644
--- a/src/bind_tolua.c
+++ b/src/bind_tolua.c
@@ -8,6 +8,7 @@
 #include "log.pkg.c"
 #include "process.pkg.c"
 #include "settings.pkg.c"
+#pragma warning(pop)
 
 void tolua_bind_open(lua_State * L) {
     tolua_eressea_open(L);
diff --git a/src/building_action.c b/src/building_action.c
index 940edb2f1..29c20a99d 100644
--- a/src/building_action.c
+++ b/src/building_action.c
@@ -28,17 +28,16 @@ without prior permission by the authors of Eressea.
 #include <string.h>
 
 typedef struct building_action {
-    struct building *b;
     char *fname;
     char *param;
 } building_action;
 
-static int lc_age(struct attrib *a)
+static int lc_age(struct attrib *a, void *owner)
 {
     building_action *data = (building_action *)a->data.v;
     const char *fname = data->fname;
     const char *fparam = data->param;
-    building *b = data->b;
+    building *b = (building *)owner;
     int result = -1;
 
     assert(b != NULL);
@@ -93,9 +92,8 @@ lc_write(const struct attrib *a, const void *owner, struct storage *store)
     building_action *data = (building_action *)a->data.v;
     const char *fname = data->fname;
     const char *fparam = data->param;
-    building *b = data->b;
 
-    write_building_reference(b, store);
+    unused_arg(owner);
     WRITE_TOK(store, fname);
     WRITE_TOK(store, fparam ? fparam : NULLSTRING);
 }
@@ -104,13 +102,17 @@ static int lc_read(struct attrib *a, void *owner, struct storage *store)
 {
     char name[NAMESIZE];
     building_action *data = (building_action *)a->data.v;
-    int result =
-        read_reference(&data->b, store, read_building_reference, resolve_building);
+    building *b = (building *)owner;
+    int result = 0;
+    if (global.data_version < ATTRIBOWNER_VERSION) {
+        result = read_reference(&b, store, read_building_reference, resolve_building);
+        assert(b == owner);
+    }
     READ_TOK(store, name, sizeof(name));
     if (strcmp(name, "tunnel_action") == 0) {
         /* E2: Weltentor has a new module, doesn't need this any longer */
         result = 0;
-        data->b = 0;
+        b = 0;
     }
     else {
         data->fname = _strdup(name);
@@ -119,14 +121,14 @@ static int lc_read(struct attrib *a, void *owner, struct storage *store)
     if (strcmp(name, "tnnL") == 0) {
         /* tunnel_action was the old Weltentore, their code has changed. ignore this object */
         result = 0;
-        data->b = 0;
+        b = 0;
     }
     if (strcmp(name, NULLSTRING) == 0)
         data->param = 0;
     else {
         data->param = _strdup(name);
     }
-    if (result == 0 && !data->b) {
+    if (result == 0 && !b) {
         return AT_READ_FAIL;
     }
     return AT_READ_OK;
@@ -143,7 +145,6 @@ void building_addaction(building * b, const char *fname, const char *param)
 {
     attrib *a = a_add(&b->attribs, a_new(&at_building_action));
     building_action *data = (building_action *)a->data.v;
-    data->b = b;
     data->fname = _strdup(fname);
     if (param) {
         data->param = _strdup(param);
diff --git a/src/items/artrewards.c b/src/items/artrewards.c
index a5aeb64c2..8b6288f61 100644
--- a/src/items/artrewards.c
+++ b/src/items/artrewards.c
@@ -45,8 +45,9 @@ OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 #define HORNDURATION 3
 #define HORNIMMUNITY 30
 
-static int age_peaceimmune(attrib * a)
+static int age_peaceimmune(attrib * a, void *owner)
 {
+    unused_arg(owner);
     return (--a->data.i > 0) ? AT_AGE_KEEP : AT_AGE_REMOVE;
 }
 
diff --git a/src/kernel/curse.c b/src/kernel/curse.c
index 09fcdb1d1..3cb39ebab 100644
--- a/src/kernel/curse.c
+++ b/src/kernel/curse.c
@@ -112,11 +112,12 @@ void curse_init(attrib * a)
     a->data.v = calloc(1, sizeof(curse));
 }
 
-int curse_age(attrib * a)
+int curse_age(attrib * a, void *owner)
 {
     curse *c = (curse *)a->data.v;
     int result = 0;
 
+    unused_arg(owner);
     c_clearflag(c, CURSE_ISNEW);
 
     if (c_flags(c) & CURSE_NOAGE) {
diff --git a/src/kernel/curse.h b/src/kernel/curse.h
index 143e73d27..263b66125 100644
--- a/src/kernel/curse.h
+++ b/src/kernel/curse.h
@@ -291,7 +291,7 @@ extern "C" {
 
     void curse_init(struct attrib *a);
     void curse_done(struct attrib *a);
-    int curse_age(struct attrib *a);
+    int curse_age(struct attrib *a, void *owner);
 
     double destr_curse(struct curse *c, int cast_level, double force);
 
diff --git a/src/kernel/item.c b/src/kernel/item.c
index aa975fb8e..e484e6c35 100644
--- a/src/kernel/item.c
+++ b/src/kernel/item.c
@@ -588,7 +588,9 @@ struct order *ord)
             use +=
             use_pooled(s, item2resource(itype), GET_RESERVE | GET_POOLED_SLACK,
             n - use);
-        rsetmoney(s->region, rmoney(s->region) + use);
+        if (s->region->land) {
+            rsetmoney(s->region, rmoney(s->region) + use);
+        }
         return 0;
     }
     return -1;                    /* use the mechanism */
diff --git a/src/kernel/region.c b/src/kernel/region.c
index aa4c86425..ed56851ee 100644
--- a/src/kernel/region.c
+++ b/src/kernel/region.c
@@ -603,8 +603,7 @@ void rsetpeasants(region * r, int value)
     if (r->land) {
         assert(value >= 0);
         r->land->peasants = value;
-    } else
-        assert(value == 0);
+    }
 }
 
 int rmoney(const region * r)
@@ -617,8 +616,7 @@ void rsethorses(const region * r, int value)
     if (r->land) {
         assert(value >= 0);
         r->land->horses = value;
-    } else
-        assert(value == 0);
+    }
 }
 
 int rhorses(const region * r)
@@ -631,8 +629,7 @@ void rsetmoney(region * r, int value)
     if (r->land) {
         assert(value >= 0);
         r->land->money = value;
-    } else
-        assert(value == 0);
+    }
 }
 
 int rherbs(const struct region *r)
@@ -645,8 +642,7 @@ void rsetherbs(const struct region *r, int value)
     if (r->land) {
         assert(value >= 0);
         r->land->herbs = (short)(value);
-    } else
-        assert(value == 0);
+    }
 }
 
 
diff --git a/src/kernel/save.c b/src/kernel/save.c
index 0fae07bb4..d4df2b6f8 100644
--- a/src/kernel/save.c
+++ b/src/kernel/save.c
@@ -20,7 +20,7 @@ OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 #include <kernel/config.h>
 #include "save.h"
 
-#include "../buildno.h"
+#include <buildno.h>
 
 #include "alchemy.h"
 #include "alliance.h"
diff --git a/src/kernel/unit.c b/src/kernel/unit.c
index 16f874b80..d82ad47ed 100644
--- a/src/kernel/unit.c
+++ b/src/kernel/unit.c
@@ -742,10 +742,11 @@ void set_level(unit * u, skill_t sk, int value)
     sk_set(add_skill(u, sk), value);
 }
 
-static int leftship_age(struct attrib *a)
+static int leftship_age(struct attrib *a, void *owner)
 {
     /* must be aged, so it doesn't affect report generation (cansee) */
     unused_arg(a);
+    unused_arg(owner);
     return AT_AGE_REMOVE;         /* remove me */
 }
 
diff --git a/src/kernel/unit.test.c b/src/kernel/unit.test.c
index fc0336c71..e72f4caed 100644
--- a/src/kernel/unit.test.c
+++ b/src/kernel/unit.test.c
@@ -331,12 +331,12 @@ static void test_age_familiar(CuTest *tc) {
     CuAssertIntEquals(tc, true, create_newfamiliar(mag, fam));
     CuAssertPtrEquals(tc, fam, get_familiar(mag));
     CuAssertPtrEquals(tc, mag, get_familiar_mage(fam));
-    a_age(&fam->attribs);
-    a_age(&mag->attribs);
+    a_age(&fam->attribs, fam);
+    a_age(&mag->attribs, mag);
     CuAssertPtrEquals(tc, fam, get_familiar(mag));
     CuAssertPtrEquals(tc, mag, get_familiar_mage(fam));
     set_number(fam, 0);
-    a_age(&mag->attribs);
+    a_age(&mag->attribs, mag);
     CuAssertPtrEquals(tc, 0, get_familiar(mag));
     test_cleanup();
 }
diff --git a/src/kernel/version.h b/src/kernel/version.h
index 81f490f34..19c564c1e 100644
--- a/src/kernel/version.h
+++ b/src/kernel/version.h
@@ -32,8 +32,9 @@
 #define EXPLICIT_CURSE_ISNEW_VERSION 347 /* CURSE_ISNEW is not reset in read/write, but in age() */
 #define SPELL_LEVEL_VERSION 348 /* f->max_spelllevel gets stored, not calculated */
 #define OWNER_3_VERSION 349 /* regions store last owner, not last alliance */
+#define ATTRIBOWNER_VERSION 350 /* all attrib_type functions know who owns the attribute */
 
-#define RELEASE_VERSION OWNER_3_VERSION /* current datafile */
+#define RELEASE_VERSION ATTRIBOWNER_VERSION /* current datafile */
 #define MIN_VERSION INTPAK_VERSION      /* minimal datafile we support */
 #define MAX_VERSION RELEASE_VERSION /* change this if we can need to read the future datafile, and we can do so */
 
diff --git a/src/laws.c b/src/laws.c
index 7dc6cd0af..5ba995e72 100755
--- a/src/laws.c
+++ b/src/laws.c
@@ -3087,7 +3087,7 @@ static building *age_building(building * b)
         }
     }
 
-    a_age(&b->attribs);
+    a_age(&b->attribs, b);
     handle_event(b->attribs, "timer", b);
 
     if (b->type->age) {
@@ -3099,7 +3099,7 @@ static building *age_building(building * b)
 
 static void age_region(region * r)
 {
-    a_age(&r->attribs);
+    a_age(&r->attribs, r);
     handle_event(r->attribs, "timer", r);
 
     if (!r->land)
@@ -3144,7 +3144,7 @@ static void ageing(void)
 
     /* Factions */
     for (f = factions; f; f = f->next) {
-        a_age(&f->attribs);
+        a_age(&f->attribs, f);
         handle_event(f->attribs, "timer", f);
     }
 
@@ -3159,7 +3159,7 @@ static void ageing(void)
         /* Einheiten */
         for (up = &r->units; *up;) {
             unit *u = *up;
-            a_age(&u->attribs);
+            a_age(&u->attribs, u);
             if (u == *up)
                 handle_event(u->attribs, "timer", u);
             if (u == *up)
@@ -3169,7 +3169,7 @@ static void ageing(void)
         /* Schiffe */
         for (sp = &r->ships; *sp;) {
             ship *s = *sp;
-            a_age(&s->attribs);
+            a_age(&s->attribs, s);
             if (s == *sp)
                 handle_event(s->attribs, "timer", s);
             if (s == *sp)
diff --git a/src/magic.c b/src/magic.c
index 0de7aa831..dc6d6e9dc 100644
--- a/src/magic.c
+++ b/src/magic.c
@@ -124,19 +124,20 @@ static double MagicPower(double force)
     return 0;
 }
 
+typedef struct icastle_data {
+    const struct building_type *type;
+    int time;
+} icastle_data;
+
 static int a_readicastle(attrib * a, void *owner, struct storage *store)
 {
     icastle_data *data = (icastle_data *)a->data.v;
-    variant bno;
     char token[32];
     READ_TOK(store, token, sizeof(token));
-    READ_INT(store, &bno.i);
-    READ_INT(store, &data->time);
-    data->building = findbuilding(bno.i);
-    if (!data->building) {
-        /* this shouldn't happen, but just in case it does: */
-        ur_add(bno, &data->building, resolve_building);
+    if (global.data_version < ATTRIBOWNER_VERSION) {
+        READ_INT(store, NULL);
     }
+    READ_INT(store, &data->time);
     data->type = bt_find(token);
     return AT_READ_OK;
 }
@@ -145,17 +146,18 @@ static void
 a_writeicastle(const attrib * a, const void *owner, struct storage *store)
 {
     icastle_data *data = (icastle_data *)a->data.v;
+    unused_arg(owner);
     WRITE_TOK(store, data->type->_name);
-    WRITE_INT(store, data->building->no);
     WRITE_INT(store, data->time);
 }
 
-static int a_ageicastle(struct attrib *a)
+static int a_ageicastle(struct attrib *a, void *owner)
 {
     icastle_data *data = (icastle_data *)a->data.v;
     if (data->time <= 0) {
-        building *b = data->building;
+        building *b = (building *)owner;
         region *r = b->region;
+        assert(owner == b);
         ADDMSG(&r->msgs, msg_message("icastle_dissolve", "building", b));
         /* remove_building lets units leave the building */
         remove_building(&r->buildings, b);
@@ -185,6 +187,17 @@ attrib_type at_icastle = {
     a_readicastle
 };
 
+void make_icastle(building *b, const building_type *btype, int timeout) {
+    attrib *a = a_add(&b->attribs, a_new(&at_icastle));
+    icastle_data *data = (icastle_data *)a->data.v;
+    data->type = btype;
+    data->time = timeout;
+}
+
+const building_type *icastle_type(const struct attrib *a) {
+    icastle_data *icastle = (icastle_data *)a->data.v;
+    return icastle->type;
+}
 /* ------------------------------------------------------------- */
 
 extern int dice(int count, int value);
@@ -2384,10 +2397,11 @@ static int read_magician(attrib * a, void *owner, struct storage *store)
     return AT_READ_OK;
 }
 
-static int age_unit(attrib * a)
+static int age_unit(attrib * a, void *owner)
 /* if unit is gone or dead, remove the attribute */
 {
     unit *u = (unit *)a->data.v;
+    unused_arg(owner);
     return (u != NULL && u->number > 0) ? AT_AGE_KEEP : AT_AGE_REMOVE;
 }
 
diff --git a/src/magic.h b/src/magic.h
index c33d9917e..257ba11c4 100644
--- a/src/magic.h
+++ b/src/magic.h
@@ -206,11 +206,8 @@ extern "C" {
     extern struct attrib_type at_reportspell;
     extern struct attrib_type at_icastle;
 
-    typedef struct icastle_data {
-        const struct building_type *type;
-        struct building *building;  /* reverse pointer to dissolve the object */
-        int time;
-    } icastle_data;
+    void make_icastle(struct building *b, const struct building_type *btype, int timeout);
+    const struct building_type *icastle_type(const struct attrib *a);
 
     /* ------------------------------------------------------------- */
     /* Kommentare:
diff --git a/src/modules/arena.c b/src/modules/arena.c
index 3b7e7c7f9..6b76a3434 100644
--- a/src/modules/arena.c
+++ b/src/modules/arena.c
@@ -212,11 +212,12 @@ order * ord)
 /**
  * Tempel der Schreie, Demo-Gebäude **/
 
-static int age_hurting(attrib * a)
+static int age_hurting(attrib * a, void *owner)
 {
     building *b = (building *)a->data.v;
     unit *u;
     int active = 0;
+    assert(owner == b);
     if (b == NULL)
         return AT_AGE_REMOVE;
     for (u = b->region->units; u; u = u->next) {
diff --git a/src/move.c b/src/move.c
index cb4d935a8..01a521391 100644
--- a/src/move.c
+++ b/src/move.c
@@ -145,9 +145,10 @@ static void shiptrail_finalize(attrib * a)
     free(a->data.v);
 }
 
-static int shiptrail_age(attrib * a)
+static int shiptrail_age(attrib * a, void *owner)
 {
     traveldir *t = (traveldir *)(a->data.v);
+    unused_arg(owner);
 
     t->age--;
     return (t->age > 0) ? AT_AGE_KEEP : AT_AGE_REMOVE;
diff --git a/src/move.test.c b/src/move.test.c
index 2688178d0..c4e9944c9 100644
--- a/src/move.test.c
+++ b/src/move.test.c
@@ -271,9 +271,9 @@ static void test_age_trails(CuTest *tc) {
     move_ship(sh, r1, r2, route);
 
     CuAssertPtrNotNull(tc, r1->attribs);
-    a_age(&r1->attribs);
+    a_age(&r1->attribs, r1);
     CuAssertPtrNotNull(tc, r1->attribs);
-    a_age(&r1->attribs);
+    a_age(&r1->attribs, r1);
     CuAssertPtrEquals(tc, 0, r1->attribs);
     free_regionlist(route);
     test_cleanup();
diff --git a/src/report.c b/src/report.c
index 6e13e834f..7b04e020f 100644
--- a/src/report.c
+++ b/src/report.c
@@ -1235,13 +1235,6 @@ static void describe(stream *out, const seen_region * sr, faction * f)
     nr_curses(out, 0, f, TYP_REGION, r);
     n = 0;
 
-    /* Produktionsreduktion */
-    a = a_find(r->attribs, &at_reduceproduction);
-    if (a) {
-        const char *str = LOC(f->locale, "nr_reduced_production");
-        paragraph(out, str, 0, 0, 0);
-    }
-
     if (edges)
         newline(out);
     for (e = edges; e; e = e->next) {
@@ -1268,6 +1261,7 @@ static void describe(stream *out, const seen_region * sr, faction * f)
             first = false;
         }
         // TODO name is localized? Works for roads anyway...
+        // TODO: creating messages during reporting makes them not show up in CR?
         msg = msg_message("nr_borderlist_postfix", "transparent object",
             e->transparent, e->name);
         bytes = (int)nr_render(msg, f->locale, bufp, size, f);
diff --git a/src/reports.c b/src/reports.c
index 24ff6dcb2..99b9f755c 100644
--- a/src/reports.c
+++ b/src/reports.c
@@ -356,8 +356,7 @@ const char **illusion)
         if (bt_illusion && b->type == bt_illusion) {
             const attrib *a = a_findc(b->attribs, &at_icastle);
             if (a != NULL) {
-                icastle_data *icastle = (icastle_data *)a->data.v;
-                *illusion = buildingtype(icastle->type, b, b->size);
+                *illusion = buildingtype(icastle_type(a), b, b->size);
             }
         }
     }
diff --git a/src/spells.c b/src/spells.c
index 4a3b81d7a..1445598d9 100644
--- a/src/spells.c
+++ b/src/spells.c
@@ -4477,13 +4477,11 @@ int sp_icastle(castorder * co)
 {
     building *b;
     const building_type *type;
-    attrib *a;
     region *r = co_get_region(co);
     unit *mage = co->magician.u;
     int cast_level = co->level;
     double power = co->force;
     spellparameter *pa = co->par;
-    icastle_data *data;
     const char *bname;
     message *msg;
     const building_type *bt_illusion = bt_find("illusioncastle");
@@ -4519,12 +4517,7 @@ int sp_icastle(castorder * co)
     building_setname(b, bname);
 
     /* TODO: Auf timeout und action_destroy umstellen */
-    a = a_add(&b->attribs, a_new(&at_icastle));
-    data = (icastle_data *)a->data.v;
-    data->type = type;
-    data->building = b;
-    data->time =
-        2 + (rng_int() % (int)(power)+1) * (rng_int() % (int)(power)+1);
+    make_icastle(b, type, 2 + (rng_int() % (int)(power)+1) * (rng_int() % (int)(power)+1));
 
     if (mage->region == r) {
         if (leave(mage, false)) {
diff --git a/src/spells.test.c b/src/spells.test.c
index 58886d991..3c773d489 100644
--- a/src/spells.test.c
+++ b/src/spells.test.c
@@ -42,7 +42,7 @@ static void test_good_dreams(CuTest *tc) {
     CuAssertTrue(tc, curse && curse->duration > 1);
     CuAssertTrue(tc, curse->effect == 1);
 
-    a_age(&r->attribs);
+    a_age(&r->attribs, r);
     CuAssertIntEquals_Msg(tc, "good dreams give +1 to allies", 1, get_modifier(u1, SK_MELEE, 11, r, false));
     CuAssertIntEquals_Msg(tc, "good dreams have no effect on non-allies", 0, get_modifier(u2, SK_MELEE, 11, r, false));
     free_castorder(&co);
@@ -67,7 +67,7 @@ static void test_dreams(CuTest *tc) {
 
     sp_gooddreams(&co);
     sp_baddreams(&co);
-    a_age(&r->attribs);
+    a_age(&r->attribs, r);
     CuAssertIntEquals_Msg(tc, "good dreams in same region as bad dreams", 1, get_modifier(u1, SK_MELEE, 11, r, false));
     CuAssertIntEquals_Msg(tc, "bad dreams in same region as good dreams", -1, get_modifier(u2, SK_MELEE, 11, r, false));
 
@@ -98,7 +98,7 @@ static void test_bad_dreams(CuTest *tc) {
     CuAssertTrue(tc, curse && curse->duration > 1);
     CuAssertTrue(tc, curse->effect == -1);
 
-    a_age(&r->attribs);
+    a_age(&r->attribs, r);
     CuAssertIntEquals_Msg(tc, "bad dreams have no effect on allies", 0, get_modifier(u1, SK_MELEE, 11, r, false));
     CuAssertIntEquals_Msg(tc, "bad dreams give -1 to non-allies", -1, get_modifier(u2, SK_MELEE, 11, r, false));
 
diff --git a/src/spells/alp.c b/src/spells/alp.c
index f86695194..d443aa063 100644
--- a/src/spells/alp.c
+++ b/src/spells/alp.c
@@ -46,7 +46,7 @@ extern const char *directions[];
 
 typedef struct alp_data {
     unit *mage;
-    unit *target;
+    unit *target; // TODO: remove, use attribute-owner?
 } alp_data;
 
 static void alp_init(attrib * a)
@@ -59,9 +59,10 @@ static void alp_done(attrib * a)
     free(a->data.v);
 }
 
-static int alp_verify(attrib * a)
+static int alp_verify(attrib * a, void *owner)
 {
     alp_data *ad = (alp_data *)a->data.v;
+    unused_arg(owner);
     if (ad->mage && ad->target)
         return 1;
     return 0;                     /* remove the attribute */
diff --git a/src/triggers/shock.test.c b/src/triggers/shock.test.c
index 8957c33fc..eae2a5004 100644
--- a/src/triggers/shock.test.c
+++ b/src/triggers/shock.test.c
@@ -1,7 +1,7 @@
 #include <platform.h>
 #include "shock.h"
-#include "../magic.h"
 
+#include <magic.h>
 #include <kernel/unit.h>
 #include <kernel/faction.h>
 #include <util/event.h>
diff --git a/src/util/attrib.c b/src/util/attrib.c
index 5c92b691e..9db46836a 100644
--- a/src/util/attrib.c
+++ b/src/util/attrib.c
@@ -252,7 +252,7 @@ attrib *a_new(const attrib_type * at)
     return a;
 }
 
-int a_age(attrib ** p)
+int a_age(attrib ** p, void *owner)
 {
     attrib **ap = p;
     /* Attribute altern, und die Entfernung (age()==0) eines Attributs
@@ -260,7 +260,7 @@ int a_age(attrib ** p)
     while (*ap) {
         attrib *a = *ap;
         if (a->type->age) {
-            int result = a->type->age(a);
+            int result = a->type->age(a, owner);
             assert(result >= 0 || !"age() returned a negative value");
             if (result == AT_AGE_REMOVE) {
                 a_remove(p, a);
diff --git a/src/util/attrib.h b/src/util/attrib.h
index c235fd67a..2703de0cb 100644
--- a/src/util/attrib.h
+++ b/src/util/attrib.h
@@ -52,7 +52,7 @@ extern "C" {
         const char *name;
         void(*initialize) (struct attrib *);
         void(*finalize) (struct attrib *);
-        int(*age) (struct attrib *);
+        int(*age) (struct attrib *, void *owner);
         /* age returns 0 if the attribute needs to be removed, !=0 otherwise */
         void(*write) (const struct attrib *, const void *owner, struct storage *);
         int(*read) (struct attrib *, void *owner, struct storage *);       /* return AT_READ_OK on success, AT_READ_FAIL if attrib needs removal */
@@ -74,7 +74,7 @@ extern "C" {
     extern void a_removeall(attrib ** a, const attrib_type * at);
     extern attrib *a_new(const attrib_type * at);
 
-    extern int a_age(attrib ** attribs);
+    extern int a_age(attrib ** attribs, void *owner);
     extern int a_read(struct storage *store, attrib ** attribs, void *owner);
     extern void a_write(struct storage *store, const attrib * attribs,
         const void *owner);
diff --git a/src/vortex.c b/src/vortex.c
index ab391f012..1d558bb49 100644
--- a/src/vortex.c
+++ b/src/vortex.c
@@ -66,9 +66,10 @@ static void a_freedirection(attrib * a)
     free(d);
 }
 
-static int a_agedirection(attrib * a)
+static int a_agedirection(attrib * a, void *owner)
 {
     spec_direction *d = (spec_direction *)(a->data.v);
+    unused_arg(owner);
     --d->duration;
     return (d->duration > 0) ? AT_AGE_KEEP : AT_AGE_REMOVE;
 }
@@ -78,7 +79,7 @@ static int a_readdirection(attrib * a, void *owner, struct storage *store)
     spec_direction *d = (spec_direction *)(a->data.v);
     char lbuf[32];
 
-    (void)owner;
+    unused_arg(owner);
     READ_INT(store, &d->x);
     READ_INT(store, &d->y);
     READ_INT(store, &d->duration);
@@ -95,7 +96,7 @@ a_writedirection(const attrib * a, const void *owner, struct storage *store)
 {
     spec_direction *d = (spec_direction *)(a->data.v);
 
-    (void)owner;
+    unused_arg(owner);
     WRITE_INT(store, d->x);
     WRITE_INT(store, d->y);
     WRITE_INT(store, d->duration);
diff --git a/src/wormhole.c b/src/wormhole.c
index 421201790..684cb8f4d 100644
--- a/src/wormhole.c
+++ b/src/wormhole.c
@@ -55,39 +55,26 @@ static int cmp_age(const void *v1, const void *v2)
     return 0;
 }
 
-typedef struct wormhole_data {
-    building *entry;
-    region *exit;
-} wormhole_data;
-
-static void wormhole_init(struct attrib *a)
+static int wormhole_age(struct attrib *a, void *owner)
 {
-    a->data.v = calloc(1, sizeof(wormhole_data));
-}
-
-static void wormhole_done(struct attrib *a)
-{
-    free(a->data.v);
-}
-
-static int wormhole_age(struct attrib *a)
-{
-    wormhole_data *data = (wormhole_data *)a->data.v;
-    int maxtransport = data->entry->size;
-    region *r = data->entry->region;
+    building *entry = (building *)owner;
+    region *exit = (region *)a->data.v;
+    int maxtransport = entry->size;
+    region *r = entry->region;
     unit *u = r->units;
 
+    unused_arg(owner);
     for (; u != NULL && maxtransport != 0; u = u->next) {
-        if (u->building == data->entry) {
+        if (u->building == entry) {
             message *m = NULL;
             if (u->number > maxtransport || has_limited_skills(u)) {
                 m = msg_message("wormhole_requirements", "unit region", u, u->region);
             }
-            else if (data->exit != NULL) {
-                move_unit(u, data->exit, NULL);
+            else if (exit != NULL) {
+                move_unit(u, exit, NULL);
                 maxtransport -= u->number;
-                m = msg_message("wormhole_exit", "unit region", u, data->exit);
-                add_message(&data->exit->msgs, m);
+                m = msg_message("wormhole_exit", "unit region", u, exit);
+                add_message(&exit->msgs, m);
             }
             if (m != NULL) {
                 add_message(&u->faction->msgs, m);
@@ -96,7 +83,7 @@ static int wormhole_age(struct attrib *a)
         }
     }
 
-    remove_building(&r->buildings, data->entry);
+    remove_building(&r->buildings, entry);
     ADDMSG(&r->msgs, msg_message("wormhole_dissolve", "region", r));
 
     /* age returns 0 if the attribute needs to be removed, !=0 otherwise */
@@ -105,9 +92,8 @@ static int wormhole_age(struct attrib *a)
 
 static void wormhole_write(const struct attrib *a, const void *owner, struct storage *store)
 {
-    wormhole_data *data = (wormhole_data *)a->data.v;
-    write_building_reference(data->entry, store);
-    write_region_reference(data->exit, store);
+    region *exit = (region *)a->data.v;
+    write_region_reference(exit, store);
 }
 
 /** conversion code, turn 573, 2008-05-23 */
@@ -125,18 +111,16 @@ static int resolve_exit(variant id, void *address)
 
 static int wormhole_read(struct attrib *a, void *owner, struct storage *store)
 {
-    wormhole_data *data = (wormhole_data *)a->data.v;
     resolve_fun resolver = (global.data_version < UIDHASH_VERSION)
         ? resolve_exit : resolve_region_id;
     read_fun reader = (global.data_version < UIDHASH_VERSION)
         ? read_building_reference : read_region_reference;
 
-    int rb =
-        read_reference(&data->entry, store, read_building_reference,
-        resolve_building);
-    int rr = read_reference(&data->exit, store, reader, resolver);
-    if (rb == 0 && rr == 0) {
-        if (!data->exit || !data->entry) {
+    if (global.data_version < ATTRIBOWNER_VERSION) {
+        READ_INT(store, NULL);
+    }
+    if (read_reference(&a->data.v, store, reader, resolver) == 0) {
+        if (!a->data.v) {
             return AT_READ_FAIL;
         }
     }
@@ -145,8 +129,8 @@ static int wormhole_read(struct attrib *a, void *owner, struct storage *store)
 
 static attrib_type at_wormhole = {
     "wormhole",
-    wormhole_init,
-    wormhole_done,
+    NULL,
+    NULL,
     wormhole_age,
     wormhole_write,
     wormhole_read,
@@ -160,12 +144,8 @@ make_wormhole(const building_type * bt_wormhole, region * r1, region * r2)
     building *b2 = new_building(bt_wormhole, r2, default_locale);
     attrib *a1 = a_add(&b1->attribs, a_new(&at_wormhole));
     attrib *a2 = a_add(&b2->attribs, a_new(&at_wormhole));
-    wormhole_data *d1 = (wormhole_data *)a1->data.v;
-    wormhole_data *d2 = (wormhole_data *)a2->data.v;
-    d1->entry = b1;
-    d2->entry = b2;
-    d1->exit = b2->region;
-    d2->exit = b1->region;
+    a1->data.v = b2->region;
+    a2->data.v = b1->region;
     b1->size = bt_wormhole->maxsize;
     b2->size = bt_wormhole->maxsize;
     ADDMSG(&r1->msgs, msg_message("wormhole_appear", "region", r1));