diff --git a/core/src/main/java/org/geysermc/geyser/registry/type/BlockMappings.java b/core/src/main/java/org/geysermc/geyser/registry/type/BlockMappings.java
index 5c4e835e4..be96fec0e 100644
--- a/core/src/main/java/org/geysermc/geyser/registry/type/BlockMappings.java
+++ b/core/src/main/java/org/geysermc/geyser/registry/type/BlockMappings.java
@@ -44,7 +44,7 @@ import java.util.Set;
 
 @Builder
 @Value
-public class BlockMappings implements DefinitionRegistry<GeyserBedrockBlock> {
+public class BlockMappings implements DefinitionRegistry<BlockDefinition> {
     GeyserBedrockBlock bedrockAir;
     BlockDefinition bedrockWater;
     BlockDefinition bedrockMovingBlock;
@@ -134,7 +134,7 @@ public class BlockMappings implements DefinitionRegistry<GeyserBedrockBlock> {
     }
 
     @Override
-    public boolean isRegistered(GeyserBedrockBlock bedrockBlock) {
+    public boolean isRegistered(BlockDefinition bedrockBlock) {
         return getDefinition(bedrockBlock.getRuntimeId()) == bedrockBlock;
     }
 }
\ No newline at end of file
diff --git a/core/src/main/java/org/geysermc/geyser/session/GeyserSession.java b/core/src/main/java/org/geysermc/geyser/session/GeyserSession.java
index 7f015a05e..25dd21662 100644
--- a/core/src/main/java/org/geysermc/geyser/session/GeyserSession.java
+++ b/core/src/main/java/org/geysermc/geyser/session/GeyserSession.java
@@ -57,7 +57,6 @@ import org.cloudburstmc.protocol.bedrock.data.command.SoftEnumUpdateType;
 import org.cloudburstmc.protocol.bedrock.data.entity.EntityFlag;
 import org.cloudburstmc.protocol.bedrock.data.inventory.ItemData;
 import org.cloudburstmc.protocol.bedrock.packet.*;
-import org.cloudburstmc.protocol.common.DefinitionRegistry;
 import org.cloudburstmc.protocol.common.util.OptionalBoolean;
 import org.geysermc.api.util.BedrockPlatform;
 import org.geysermc.api.util.InputMode;
@@ -1466,7 +1465,7 @@ public class GeyserSession implements GeyserConnection, GeyserCommandSource {
 
     private void startGame() {
         this.upstream.getCodecHelper().setItemDefinitions(this.itemMappings);
-        this.upstream.getCodecHelper().setBlockDefinitions((DefinitionRegistry) this.blockMappings); //FIXME
+        this.upstream.getCodecHelper().setBlockDefinitions(this.blockMappings);
         this.upstream.getCodecHelper().setCameraPresetDefinitions(CameraDefinitions.CAMERA_DEFINITIONS);
 
         StartGamePacket startGamePacket = new StartGamePacket();