diff --git a/curriculum/challenges/english/02-javascript-algorithms-and-data-structures/basic-algorithm-scripting/falsy-bouncer.md b/curriculum/challenges/english/02-javascript-algorithms-and-data-structures/basic-algorithm-scripting/falsy-bouncer.md
index bdeca316a4e..fb62b8eddf0 100644
--- a/curriculum/challenges/english/02-javascript-algorithms-and-data-structures/basic-algorithm-scripting/falsy-bouncer.md
+++ b/curriculum/challenges/english/02-javascript-algorithms-and-data-structures/basic-algorithm-scripting/falsy-bouncer.md
@@ -8,7 +8,7 @@ dashedName: falsy-bouncer
 
 # --description--
 
-Remove all falsy values from an array.
+Remove all falsy values from an array. Return a new array; do not mutate the original array.
 
 Falsy values in JavaScript are `false`, `null`, `0`, `""`, `undefined`, and `NaN`.
 
@@ -40,6 +40,14 @@ assert.deepEqual(bouncer([false, null, 0, NaN, undefined, '']), []);
 assert.deepEqual(bouncer([null, NaN, 1, 2, undefined]), [1, 2]);
 ```
 
+You should not mutate `arr`.
+
+```js
+const arr = ['a', false, 0, 'Naomi'];
+bouncer(arr);
+assert.deepEqual(arr, ['a', false, 0, 'Naomi'])
+```
+
 # --seed--
 
 ## --seed-contents--