I agree that good code would allow for the possibility that there may be more than one even AND more than one odd number.

I tried that before, and it was returning both even and odds. I tried it again and the same exact code I previously wrote works now. No clue what was different, but it works! Thank you!

Use console.log(numbers); Each test have exactly one number that's not like the others.

I'm using javascript, and in every single test it is giving tests that have both even numbers and odd numbers. I have read the description over and over, and it looks like it's supposed to give either one even in a group of odds, or one odd in a group of evens. Maybe I'm missing something, but I don't think it's supposed to give multiple of each.

From the description: for other input raise an error.

Also: If you want to paste multiple lines of code please surround them by a line of three backticks (see https://help.github.com/articles/basic-writing-and-formatting-syntax/#quoting-code).

Lesson learned: read instructions very well haha