Grabbed dndbeyond's source code

```
~/go/bin/sourcemapper -output ddb -jsurl https://media.dndbeyond.com/character-app/static/js/main.90aa78c5.js
```

ddb_main/packages/rules-engine/es/diceRolls/simulators.js

@@ -0,0 +1,26 @@
+import { HelperUtils } from '../engine/Helper';
+/**
+ *
+ * @param rollGroupContractProps
+ * @param simulatedRollResultCount
+ */
+export function simulateRollGroupContract(rollGroupContractProps, simulatedRollResultCount = 0) {
+    var _a;
+    let rollResults = [];
+    let lastRoll = null;
+    for (let i = 0; i < simulatedRollResultCount; i++) {
+        const rollResultContract = simulateRollResultContract({
+            nextRollKey: (_a = lastRoll === null || lastRoll === void 0 ? void 0 : lastRoll.rollKey) !== null && _a !== void 0 ? _a : null,
+        });
+        rollResults.push(rollResultContract);
+        lastRoll = rollResultContract;
+    }
+    return Object.assign({ groupKey: HelperUtils.generateGuid(), nextGroupKey: null, rollResults }, rollGroupContractProps);
+}
+/**
+ *
+ * @param rollResultContractProps
+ */
+export function simulateRollResultContract(rollResultContractProps) {
+    return Object.assign({ rollKey: HelperUtils.generateGuid(), nextRollKey: null, rollTotal: null, rollValues: [], assignedValue: null }, rollResultContractProps);
+}