diff --git a/data/battle_scripts_1.s b/data/battle_scripts_1.s
index 4104f1dd57..9c4172861f 100644
--- a/data/battle_scripts_1.s
+++ b/data/battle_scripts_1.s
@@ -2234,6 +2234,7 @@ BattleScript_EffectAbsorb::
 	resultmessage
 	waitmessage 0x40
 	setdrainedhp
+	manipulatedamage DMG_BIG_ROOT
 	orword gHitMarker, HITMARKER_IGNORE_SUBSTITUTE
 	jumpifability BS_TARGET, ABILITY_LIQUID_OOZE, BattleScript_AbsorbLiquidOoze
 	setbyte cMULTISTRING_CHOOSER, 0x0
@@ -2361,6 +2362,7 @@ BattleScript_DreamEaterWorked:
 	resultmessage
 	waitmessage 0x40
 	setdrainedhp
+	manipulatedamage DMG_BIG_ROOT
 	orword gHitMarker, HITMARKER_IGNORE_SUBSTITUTE
 	healthbarupdate BS_ATTACKER
 	datahpupdate BS_ATTACKER
diff --git a/src/battle_script_commands.c b/src/battle_script_commands.c
index df3e8da3d9..3d7f2858a7 100644
--- a/src/battle_script_commands.c
+++ b/src/battle_script_commands.c
@@ -8877,15 +8877,16 @@ static void Cmd_stockpiletohpheal(void)
     }
 }
 
+// Sign change for drained HP handled in GetDrainedBigRootHp
 static void Cmd_setdrainedhp(void)
 {
     if (gBattleMoves[gCurrentMove].argument != 0)
-        gBattleMoveDamage = -(gHpDealt * gBattleMoves[gCurrentMove].argument / 100);
+        gBattleMoveDamage = (gHpDealt * gBattleMoves[gCurrentMove].argument / 100);
     else
-        gBattleMoveDamage = -(gHpDealt / 2);
+        gBattleMoveDamage = (gHpDealt / 2);
 
     if (gBattleMoveDamage == 0)
-        gBattleMoveDamage = -1;
+        gBattleMoveDamage = 1;
 
     gBattlescriptCurrInstr++;
 }