diff --git a/src/module/rolls/check-factory.ts b/src/module/rolls/check-factory.ts
index 2b3556b7..7e4997b1 100644
--- a/src/module/rolls/check-factory.ts
+++ b/src/module/rolls/check-factory.ts
@@ -36,12 +36,8 @@ class CheckFactory {
     async execute(): Promise<ChatMessage | unknown> {
         const rollCls = CONFIG.Dice.rolls[0];
 
-        const formula = [
-            "ds",
-            this.createTargetValueTerm(),
-            this.createCritTerm(),
-            this.createSlayingDiceTerm(),
-        ].filterJoin("");
+        const innerFormula = ["ds", this.createTargetValueTerm(), this.createCritTerm()].filterJoin("");
+        const formula = this.checkOptions.useSlayingDice ? `{${innerFormula}}x` : innerFormula;
         const roll = new rollCls(formula);
 
         const rollModeTemplate = this.checkOptions.rollMode;
@@ -62,15 +58,11 @@ class CheckFactory {
         const maxCritRequired = this.checkOptions.maxCritSuccess !== defaultCheckOptions.maxCritSuccess;
 
         if (minCritRequired || maxCritRequired) {
-            return "c" + (this.checkOptions.maxCritSuccess ?? "") + "," + (this.checkOptions.minCritFailure ?? "");
+            return "c" + (this.checkOptions.maxCritSuccess ?? "") + ":" + (this.checkOptions.minCritFailure ?? "");
         } else {
             return null;
         }
     }
-
-    createSlayingDiceTerm(): string | null {
-        return this.checkOptions.useSlayingDice ? "x" : null;
-    }
 }
 
 /**