diff --git a/src/main/java/net/neoforged/neoforge/common/NeoForge.java b/src/main/java/net/neoforged/neoforge/common/NeoForge.java
index a8ea91f29e..9242ea437f 100644
--- a/src/main/java/net/neoforged/neoforge/common/NeoForge.java
+++ b/src/main/java/net/neoforged/neoforge/common/NeoForge.java
@@ -15,7 +15,7 @@ public class NeoForge {
      * Also known as the "game" bus.
      */
     public static final IEventBus EVENT_BUS = BusBuilder.builder().startShutdown().classChecker(eventType -> {
-        if (eventType.isAssignableFrom(IModBusEvent.class)) {
+        if (IModBusEvent.class.isAssignableFrom(eventType)) {
             throw new IllegalArgumentException("IModBusEvent events are not allowed on the common NeoForge bus! Use a mod bus instead.");
         }
     }).build();
diff --git a/tests/src/main/java/net/neoforged/neoforge/oldtest/block/SlipperinessTest.java b/tests/src/main/java/net/neoforged/neoforge/oldtest/block/SlipperinessTest.java
index ceab2c4fd9..87e51c2cba 100644
--- a/tests/src/main/java/net/neoforged/neoforge/oldtest/block/SlipperinessTest.java
+++ b/tests/src/main/java/net/neoforged/neoforge/oldtest/block/SlipperinessTest.java
@@ -22,7 +22,7 @@
 import net.neoforged.neoforge.registries.RegisterEvent;
 
 @Mod(SlipperinessTest.MOD_ID)
-@EventBusSubscriber
+@EventBusSubscriber(bus = EventBusSubscriber.Bus.MOD)
 public class SlipperinessTest {
     static final String MOD_ID = "slipperiness_test";
     static final String BLOCK_ID = "test_block";