diff --git a/seed/challenges/01-front-end-development-certification/advanced-bonfires.json b/seed/challenges/01-front-end-development-certification/advanced-bonfires.json
index 57b1e76c08..197d95af9d 100644
--- a/seed/challenges/01-front-end-development-certification/advanced-bonfires.json
+++ b/seed/challenges/01-front-end-development-certification/advanced-bonfires.json
@@ -96,11 +96,16 @@
         "function sym(args) {\n  var index = -1;\n  var length = arguments.length;\n  var result;\n  while (++index < length) {\n    var array = arguments[index];\n    result = result ? diff(result, array).concat(diff(array, result)) : array;\n  }\n  return result ? uniq(result) : [];\n}\n\nfunction uniq(arr) {\n  var h = Object.create(null);\n  var u = [];\n  arr.forEach(function(v) {\n    if (v in h) return;\n    h[v] = true;\n    u.push(v);\n  });\n  return u;\n}\n\nfunction diff(a, b) {\n  var h = Object.create(null);\n  b.forEach(function(v) {\n    h[v] = true;  \n  });\n  return a.filter(function(v) { return !(v in h);});\n}\nsym([1, 2, 3], [5, 2, 1, 4]);\n"
       ],
       "tests": [
-        "assert.deepEqual(sym([1, 2, 3], [5, 2, 1, 4]).sort(), [3, 4, 5], 'message: <code>sym([1, 2, 3], [5, 2, 1, 4])</code> should return <code>[3, 5, 4]</code>.');",
-        "assert.deepEqual(sym([1, 2, 5], [2, 3, 5], [3, 4, 5]).sort(), [1, 4, 5], 'message: <code>sym([1, 2, 5], [2, 3, 5], [3, 4, 5])</code> should return <code>[1, 4, 5]</code>');",
-        "assert.deepEqual(sym([1, 1, 2, 5], [2, 2, 3, 5], [3, 4, 5, 5]).sort(), [1, 4, 5], 'message: <code>sym([1, 1, 2, 5], [2, 2, 3, 5], [3, 4, 5, 5])</code> should return <code>[1, 4, 5]</code>.');",
-        "assert.deepEqual(sym([3, 3, 3, 2, 5], [2, 1, 5, 7], [3, 4, 6, 6], [1, 2, 3]).sort(), [2, 3, 4, 6, 7], 'message: <code>sym([3, 3, 3, 2, 5], [2, 1, 5, 7], [3, 4, 6, 6], [1, 2, 3])</code> should return <code>[7, 4, 6, 2, 3]</code>.');",
-        "assert.deepEqual(sym([3, 3, 3, 2, 5], [2, 1, 5, 7], [3, 4, 6, 6], [1, 2, 3], [5, 3, 9, 8], [1]).sort(), [1, 2, 4, 5, 6, 7, 8, 9], 'message: <code>sym([3, 3, 3, 2, 5], [2, 1, 5, 7], [3, 4, 6, 6], [1, 2, 3], [5, 3, 9, 8], [1])</code> should return <code>[1, 2, 4, 5, 6, 7, 8, 9]</code>')"
+        "assert.sameMembers(sym([1, 2, 3], [5, 2, 1, 4]), [3, 4, 5], 'message: <code>sym([1, 2, 3], [5, 2, 1, 4])</code> should return <code>[3, 4, 5]</code>.');",
+        "assert.equal(sym([1, 2, 3], [5, 2, 1, 4]).length, 3, 'message: <code>sym([1, 2, 3], [5, 2, 1, 4])</code> should contain only three elements.');",
+        "assert.sameMembers(sym([1, 2, 5], [2, 3, 5], [3, 4, 5]), [1, 4, 5], 'message: <code>sym([1, 2, 5], [2, 3, 5], [3, 4, 5])</code> should return <code>[1, 4, 5]</code>');",
+        "assert.equal(sym([1, 2, 5], [2, 3, 5], [3, 4, 5]).length, 3, 'message: <code>sym([1, 2, 5], [2, 3, 5], [3, 4, 5])</code> should contain only three elements.');",
+        "assert.sameMembers(sym([1, 1, 2, 5], [2, 2, 3, 5], [3, 4, 5, 5]), [1, 4, 5], 'message: <code>sym([1, 1, 2, 5], [2, 2, 3, 5], [3, 4, 5, 5])</code> should return <code>[1, 4, 5]</code>.');",
+        "assert.equal(sym([1, 1, 2, 5], [2, 2, 3, 5], [3, 4, 5, 5]).length, 3, 'message: <code>sym([1, 1, 2, 5], [2, 2, 3, 5], [3, 4, 5, 5])</code> should contain only three elements.');",
+        "assert.sameMembers(sym([3, 3, 3, 2, 5], [2, 1, 5, 7], [3, 4, 6, 6], [1, 2, 3]), [2, 3, 4, 6, 7], 'message: <code>sym([3, 3, 3, 2, 5], [2, 1, 5, 7], [3, 4, 6, 6], [1, 2, 3])</code> should return <code>[2, 3, 4, 6, 7]</code>.');",
+        "assert.equal(sym([3, 3, 3, 2, 5], [2, 1, 5, 7], [3, 4, 6, 6], [1, 2, 3]).length, 5, 'message: <code>sym([3, 3, 3, 2, 5], [2, 1, 5, 7], [3, 4, 6, 6], [1, 2, 3])</code> should contain only five elements.');",
+        "assert.sameMembers(sym([3, 3, 3, 2, 5], [2, 1, 5, 7], [3, 4, 6, 6], [1, 2, 3], [5, 3, 9, 8], [1]), [1, 2, 4, 5, 6, 7, 8, 9], 'message: <code>sym([3, 3, 3, 2, 5], [2, 1, 5, 7], [3, 4, 6, 6], [1, 2, 3], [5, 3, 9, 8], [1])</code> should return <code>[1, 2, 4, 5, 6, 7, 8, 9]</code>.');",
+        "assert.equal(sym([3, 3, 3, 2, 5], [2, 1, 5, 7], [3, 4, 6, 6], [1, 2, 3], [5, 3, 9, 8], [1]).length, 8, 'message: <code>sym([3, 3, 3, 2, 5], [2, 1, 5, 7], [3, 4, 6, 6], [1, 2, 3], [5, 3, 9, 8], [1])</code> should contain only eight elements.');"
       ],
       "type": "bonfire",
       "MDNlinks": [