diff --git a/test/test_runner_battle.c b/test/test_runner_battle.c
index c009219e26..a116dd0b52 100644
--- a/test/test_runner_battle.c
+++ b/test/test_runner_battle.c
@@ -444,7 +444,7 @@ u32 RandomWeightedArray(enum RandomTag tag, u32 sum, u32 n, const u8 *weights)
     if (sum == 0)
         Test_ExitWithResult(TEST_RESULT_ERROR, SourceLine(0), ":LRandomWeightedArray called with zero sum");
 
-    if (gCurrentTurnActionNumber < gBattlersCount)
+    if (gCurrentTurnActionNumber < gBattlersCount || tag == RNG_SHELL_SIDE_ARM)
     {
         u32 battlerId = gBattlerByTurnOrder[gCurrentTurnActionNumber];
         turn = &DATA.battleRecordTurns[gBattleResults.battleTurnCounter][battlerId];
@@ -2216,6 +2216,17 @@ void Move(u32 sourceLine, struct BattlePokemon *battler, struct MoveContext ctx)
         DATA.battleRecordTurns[DATA.turns][battlerId].secondaryEffect = 1 + ctx.secondaryEffect;
     if (ctx.explicitRNG)
         DATA.battleRecordTurns[DATA.turns][battlerId].rng = ctx.rng;
+    
+    u32 shellSideArmCount = 0;
+    for (u32 i = 0; i < STATE->battlersCount; i++)
+    {
+        if (DATA.battleRecordTurns[DATA.turns][i].rng.tag == RNG_SHELL_SIDE_ARM)
+        {
+            shellSideArmCount++;
+            if (shellSideArmCount > 1)
+                Test_ExitWithResult(TEST_RESULT_ERROR, SourceLine(0), ":L Tried to use fixed RNG for multiple Shell Side Arm moves in the same turn");
+        }
+    }
 
     if (!(DATA.actionBattlers & (1 << battlerId)))
     {