diff --git a/common/combat/damage.packet.js b/common/combat/damage.packet.js
index a67165a..f1f7b8b 100644
--- a/common/combat/damage.packet.js
+++ b/common/combat/damage.packet.js
@@ -10,7 +10,7 @@ export class DamagePacket extends EntityPacket {
         damageSpec: {
           affinity: 'uint8',
         },
-        from: 'string',
+        from: 'uint32',
         isDamage: 'bool',
       },
     ];
diff --git a/common/combat/vulnerable.trait.js b/common/combat/vulnerable.trait.js
index a98c919..56af30c 100644
--- a/common/combat/vulnerable.trait.js
+++ b/common/combat/vulnerable.trait.js
@@ -205,7 +205,7 @@ export class Vulnerable extends Trait {
             isDamage,
             amount,
             damageSpec,
-            from: entity.instanceUuid,
+            from: entity.numericUid,
           };
           this.entity.emit('tookDamage', damage);
         }
diff --git a/common/packets/self-entity.packet.js b/common/packets/self-entity.packet.js
index 4408080..f0cdff7 100644
--- a/common/packets/self-entity.packet.js
+++ b/common/packets/self-entity.packet.js
@@ -5,7 +5,7 @@ export class SelfEntityPacket extends Packet {
   static get schema() {
     return {
       ...super.schema,
-      data: 'string',
+      data: 'uint32',
     };
   }
 
diff --git a/server/game.js b/server/game.js
index 6ba23d1..d0837ac 100644
--- a/server/game.js
+++ b/server/game.js
@@ -59,7 +59,7 @@ export default class Game {
     this.room.addEntityToLayer(entity, 0);
     // Initial information.
     const packets = this.synchronizer.packetsForUpdate(true);
-    packets.unshift(new SelfEntityPacket(entity.instanceUuid));
+    packets.unshift(new SelfEntityPacket(entity.numericUid));
     entity.inform(packets);
     // Listen for events.
     socket.on('packet', this.createPacketListener(socket));