diff --git a/src/data/mystery-encounters/encounters/a-trainers-test-encounter.ts b/src/data/mystery-encounters/encounters/a-trainers-test-encounter.ts
index 688973d6be3..7f11064f392 100644
--- a/src/data/mystery-encounters/encounters/a-trainers-test-encounter.ts
+++ b/src/data/mystery-encounters/encounters/a-trainers-test-encounter.ts
@@ -174,7 +174,7 @@ export const ATrainersTestEncounter: MysteryEncounter =
           tier: EggTier.GREAT
         };
         encounter.setDialogueToken("eggType", i18next.t(`${namespace}.eggTypes.rare`));
-        setEncounterRewards(scene, { fillRemaining: false, rerollMultiplier: 0 }, [eggOptions]);
+        setEncounterRewards(scene, { fillRemaining: false, rerollMultiplier: -1 }, [eggOptions]);
         leaveEncounterWithoutBattle(scene);
       }
     )
diff --git a/src/modifier/modifier-type.ts b/src/modifier/modifier-type.ts
index b807dc8b7c6..ed1a6d4aea5 100644
--- a/src/modifier/modifier-type.ts
+++ b/src/modifier/modifier-type.ts
@@ -2048,6 +2048,7 @@ export interface CustomModifierSettings {
   guaranteedModifierTypeOptions?: ModifierTypeOption[];
   guaranteedModifierTypeFuncs?: ModifierTypeFunc[];
   fillRemaining?: boolean;
+  /** Set to negative value to disable rerolls completely in shop */
   rerollMultiplier?: number;
   allowLuckUpgrades?: boolean;
 }
diff --git a/src/phases/mystery-encounter-phases.ts b/src/phases/mystery-encounter-phases.ts
index f5539a6f0bb..a3672438c55 100644
--- a/src/phases/mystery-encounter-phases.ts
+++ b/src/phases/mystery-encounter-phases.ts
@@ -524,7 +524,7 @@ export class MysteryEncounterRewardsPhase extends Phase {
       encounter.doEncounterRewards(this.scene);
     } else if (this.addHealPhase) {
       this.scene.tryRemovePhase(p => p instanceof SelectModifierPhase);
-      this.scene.unshiftPhase(new SelectModifierPhase(this.scene, 0, undefined, { fillRemaining: false, rerollMultiplier: 0 }));
+      this.scene.unshiftPhase(new SelectModifierPhase(this.scene, 0, undefined, { fillRemaining: false, rerollMultiplier: -1 }));
     }
 
     this.scene.pushPhase(new PostMysteryEncounterPhase(this.scene));
diff --git a/src/phases/select-modifier-phase.ts b/src/phases/select-modifier-phase.ts
index 8e34f6ce9bd..cb280a2ca80 100644
--- a/src/phases/select-modifier-phase.ts
+++ b/src/phases/select-modifier-phase.ts
@@ -74,7 +74,7 @@ export class SelectModifierPhase extends BattlePhase {
         switch (cursor) {
         case 0:
           const rerollCost = this.getRerollCost(typeOptions, this.scene.lockModifierTiers);
-          if (rerollCost === 0 || this.scene.money < rerollCost) {
+          if (rerollCost < 0 || this.scene.money < rerollCost) {
             this.scene.ui.playError();
             return false;
           } else {
@@ -241,7 +241,17 @@ export class SelectModifierPhase extends BattlePhase {
     } else {
       baseValue = 250;
     }
-    const multiplier = !isNullOrUndefined(this.customModifierSettings?.rerollMultiplier) ? this.customModifierSettings!.rerollMultiplier! : 1;
+
+    let multiplier = 1;
+    if (!isNullOrUndefined(this.customModifierSettings?.rerollMultiplier)) {
+      if (this.customModifierSettings!.rerollMultiplier! < 0) {
+        // Completely overrides reroll cost to -1 and early exits
+        return -1;
+      }
+
+      // Otherwise, continue with custom multiplier
+      multiplier = this.customModifierSettings!.rerollMultiplier!;
+    }
     return Math.min(Math.ceil(this.scene.currentBattle.waveIndex / 10) * baseValue * Math.pow(2, this.rerollCount) * multiplier, Number.MAX_SAFE_INTEGER);
   }
 
diff --git a/src/ui/modifier-select-ui-handler.ts b/src/ui/modifier-select-ui-handler.ts
index 8e27a4352b5..9f1d6d24a63 100644
--- a/src/ui/modifier-select-ui-handler.ts
+++ b/src/ui/modifier-select-ui-handler.ts
@@ -31,6 +31,10 @@ export default class ModifierSelectUiHandler extends AwaitableUiHandler {
 
   private rowCursor: integer = 0;
   private player: boolean;
+  /**
+   * If reroll cost is negative, it is assumed there are 0 items in the shop.
+   * It will cause reroll button to be disabled, and a "Continue" button to show in the place of shop items
+   */
   private rerollCost: integer;
   private transferButtonWidth: integer;
   private checkButtonWidth: integer;
@@ -265,7 +269,7 @@ export default class ModifierSelectUiHandler extends AwaitableUiHandler {
       this.continueButtonContainer.setAlpha(0);
       this.rerollButtonContainer.setVisible(true);
       this.checkButtonContainer.setVisible(true);
-      this.continueButtonContainer.setVisible(this.rerollCost === 0);
+      this.continueButtonContainer.setVisible(this.rerollCost < 0);
       this.lockRarityButtonContainer.setVisible(canLockRarities);
 
       this.scene.tweens.add({
@@ -276,7 +280,7 @@ export default class ModifierSelectUiHandler extends AwaitableUiHandler {
 
       this.scene.tweens.add({
         targets: [this.rerollButtonContainer],
-        alpha: this.rerollCost === 0 ? 0.5 : 1,
+        alpha: this.rerollCost < 0 ? 0.5 : 1,
         duration: 250
       });
 
@@ -537,6 +541,13 @@ export default class ModifierSelectUiHandler extends AwaitableUiHandler {
   }
 
   updateRerollCostText(): void {
+    const rerollDisabled = this.rerollCost < 0;
+    if (rerollDisabled) {
+      this.rerollCostText.setVisible(false);
+      return;
+    } else {
+      this.rerollCostText.setVisible(true);
+    }
     const canReroll = this.scene.money >= this.rerollCost;
 
     const formattedMoney = Utils.formatMoney(this.scene.moneyFormat, this.rerollCost);