diff --git a/common/src/main/java/com/viaversion/viabackwards/protocol/v1_20_5to1_20_3/rewriter/EntityPacketRewriter1_20_5.java b/common/src/main/java/com/viaversion/viabackwards/protocol/v1_20_5to1_20_3/rewriter/EntityPacketRewriter1_20_5.java
index ac9c8b7e..9775c982 100644
--- a/common/src/main/java/com/viaversion/viabackwards/protocol/v1_20_5to1_20_3/rewriter/EntityPacketRewriter1_20_5.java
+++ b/common/src/main/java/com/viaversion/viabackwards/protocol/v1_20_5to1_20_3/rewriter/EntityPacketRewriter1_20_5.java
@@ -243,14 +243,26 @@ public final class EntityPacketRewriter1_20_5 extends EntityRewriter<Clientbound
 
         protocol.registerClientbound(ClientboundPackets1_20_5.UPDATE_MOB_EFFECT, wrapper -> {
             wrapper.passthrough(Types.VAR_INT); // Entity ID
-            wrapper.passthrough(Types.VAR_INT); // Effect ID
+            final int effectId = wrapper.passthrough(Types.VAR_INT);
 
             final int amplifier = wrapper.read(Types.VAR_INT);
             wrapper.write(Types.BYTE, (byte) MathUtil.clamp(amplifier, Byte.MIN_VALUE, Byte.MAX_VALUE));
 
             wrapper.passthrough(Types.VAR_INT); // Duration
             wrapper.passthrough(Types.BYTE); // Flags
-            wrapper.write(Types.OPTIONAL_COMPOUND_TAG, null); // Add empty factor data
+
+            if (effectId == 32) { // Darkness, keep a stable effect
+                final CompoundTag factorData = new CompoundTag();
+                factorData.putInt("padding_duration", 22);
+                factorData.putBoolean("had_effect_last_tick", true);
+                factorData.putFloat("factor_previous_frame", 0);
+                factorData.putFloat("factor_start", 1);
+                factorData.putFloat("factor_target", 1);
+                factorData.putFloat("factor_current", 1);
+                wrapper.write(Types.OPTIONAL_COMPOUND_TAG, factorData);
+            } else {
+                wrapper.write(Types.OPTIONAL_COMPOUND_TAG, null);
+            }
         });
 
         protocol.registerClientbound(ClientboundPackets1_20_5.UPDATE_ATTRIBUTES, wrapper -> {