diff --git a/seed/challenges/intermediate-bonfires.json b/seed/challenges/intermediate-bonfires.json
index 6d90d9fdd77..b979f1369fe 100644
--- a/seed/challenges/intermediate-bonfires.json
+++ b/seed/challenges/intermediate-bonfires.json
@@ -50,7 +50,7 @@
       "id": "a5de63ebea8dbee56860f4f2",
       "title": "Diff Two Arrays",
       "description": [
-        "Compare two arrays and return a new array with any items not found in both of the original arrays.",
+        "Compare two arrays and return a new array with any items only found in one of the original arrays.",
         "Remember to use <a href='//github.com/FreeCodeCamp/freecodecamp/wiki/How-to-get-help-when-you-get-stuck' target='_blank'>Read-Search-Ask</a> if you get stuck. Try to pair program. Write your own code."
       ],
       "challengeSeed": [
@@ -64,13 +64,13 @@
       ],
       "tests": [
         "assert(typeof(diff([1, 2, 3, 5], [1, 2, 3, 4, 5])) === \"object\", 'message: <code>diff()</code> should return an array.');",
-        "assert.deepEqual(diff([\"diorite\", \"andesite\", \"grass\", \"dirt\", \"pink wool\", \"dead shrub\"], [\"diorite\", \"andesite\", \"grass\", \"dirt\", \"dead shrub\"]), [\"pink wool\"], 'message: <code>[\"diorite\", \"andesite\", \"grass\", \"dirt\", \"pink wool\", \"dead shrub\"], [\"diorite\", \"andesite\", \"grass\", \"dirt\", \"dead shrub\"]</code> should return <code>[\"pink wool\"]</code>.');",
-        "assert.includeMembers(diff([\"andesite\", \"grass\", \"dirt\", \"pink wool\", \"dead shrub\"], [\"diorite\", \"andesite\", \"grass\", \"dirt\", \"dead shrub\"]), [\"diorite\", \"pink wool\"], 'message: <code>[\"andesite\", \"grass\", \"dirt\", \"pink wool\", \"dead shrub\"], [\"diorite\", \"andesite\", \"grass\", \"dirt\", \"dead shrub\"]</code> should return <code>[\"diorite\", \"pink wool\"]</code>.');",
-        "assert.deepEqual(diff([\"andesite\", \"grass\", \"dirt\", \"dead shrub\"], [\"andesite\", \"grass\", \"dirt\", \"dead shrub\"]), [], 'message: <code>[\"andesite\", \"grass\", \"dirt\", \"dead shrub\"], [\"andesite\", \"grass\", \"dirt\", \"dead shrub\"]</code> should return <code>[]</code>.');",
-        "assert.deepEqual(diff([1, 2, 3, 5], [1, 2, 3, 4, 5]), [4], 'message: <code>[1, 2, 3, 5], [1, 2, 3, 4, 5]</code> should return <code>[4]</code>.');",
-        "assert.includeMembers(diff([1, \"calf\", 3, \"piglet\"], [1, \"calf\", 3, 4]), [\"piglet\", 4], 'message: <code>[1, \"calf\", 3, \"piglet\"], [1, \"calf\", 3, 4]</code> should return <code>[\"piglet\", 4]</code>.');",
-        "assert.deepEqual(diff([], [\"snuffleupagus\", \"cookie monster\", \"elmo\"]), [\"snuffleupagus\", \"cookie monster\", \"elmo\"], 'message: <code>[], [\"snuffleupagus\", \"cookie monster\", \"elmo\"]</code> should return <code>[\"snuffleupagus\", \"cookie monster\", \"elmo\"]</code>.');",
-        "assert.includeMembers(diff([1, \"calf\", 3, \"piglet\"], [7, \"filly\"]), [1, \"calf\", 3, \"piglet\", 7, \"filly\"], 'message: <code>[1, \"calf\", 3, \"piglet\"], [7, \"filly\"]</code> should return <code>[1, \"calf\", 3, \"piglet\", 7, \"filly\"]</code>.');"
+        "assert.sameMembers(diff([\"diorite\", \"andesite\", \"grass\", \"dirt\", \"pink wool\", \"dead shrub\"], [\"diorite\", \"andesite\", \"grass\", \"dirt\", \"dead shrub\"]), [\"pink wool\"], 'message: <code>[\"diorite\", \"andesite\", \"grass\", \"dirt\", \"pink wool\", \"dead shrub\"], [\"diorite\", \"andesite\", \"grass\", \"dirt\", \"dead shrub\"]</code> should return <code>[\"pink wool\"]</code>.');",
+        "assert.sameMembers(diff([\"andesite\", \"grass\", \"dirt\", \"pink wool\", \"dead shrub\"], [\"diorite\", \"andesite\", \"grass\", \"dirt\", \"dead shrub\"]), [\"diorite\", \"pink wool\"], 'message: <code>[\"andesite\", \"grass\", \"dirt\", \"pink wool\", \"dead shrub\"], [\"diorite\", \"andesite\", \"grass\", \"dirt\", \"dead shrub\"]</code> should return <code>[\"diorite\", \"pink wool\"]</code>.');",
+        "assert.sameMembers(diff([\"andesite\", \"grass\", \"dirt\", \"dead shrub\"], [\"andesite\", \"grass\", \"dirt\", \"dead shrub\"]), [], 'message: <code>[\"andesite\", \"grass\", \"dirt\", \"dead shrub\"], [\"andesite\", \"grass\", \"dirt\", \"dead shrub\"]</code> should return <code>[]</code>.');",
+        "assert.sameMembers(diff([1, 2, 3, 5], [1, 2, 3, 4, 5]), [4], 'message: <code>[1, 2, 3, 5], [1, 2, 3, 4, 5]</code> should return <code>[4]</code>.');",
+        "assert.sameMembers(diff([1, \"calf\", 3, \"piglet\"], [1, \"calf\", 3, 4]), [\"piglet\", 4], 'message: <code>[1, \"calf\", 3, \"piglet\"], [1, \"calf\", 3, 4]</code> should return <code>[\"piglet\", 4]</code>.');",
+        "assert.sameMembers(diff([], [\"snuffleupagus\", \"cookie monster\", \"elmo\"]), [\"snuffleupagus\", \"cookie monster\", \"elmo\"], 'message: <code>[], [\"snuffleupagus\", \"cookie monster\", \"elmo\"]</code> should return <code>[\"snuffleupagus\", \"cookie monster\", \"elmo\"]</code>.');",
+        "assert.sameMembers(diff([1, \"calf\", 3, \"piglet\"], [7, \"filly\"]), [1, \"calf\", 3, \"piglet\", 7, \"filly\"], 'message: <code>[1, \"calf\", 3, \"piglet\"], [7, \"filly\"]</code> should return <code>[1, \"calf\", 3, \"piglet\", 7, \"filly\"]</code>.');"
       ],
       "MDNlinks": [
         "Comparison Operators",