Basically,  2 small questions...

1: Has anyone completed the "No-CHAD challenge yet"?

2: How exactly does "only red babies" work? Like does it start counting when I get 4 red babies?

I'll answer the second one, You have to complete ANY level of your choice using 4 of the following: Lil Chad, Cube of Meat, Spike Baby, Tooth n Nail, Lil Loki or Double Baby. 

1: Yes.

2: Just complete a single level with only red-colored babies, which is basically those anthropomorphine mentioned.

1. yes. just spam lil loki till middle horn

2. yeah just use any red babies prefer chad, lil loki, cube of meat, and spike baby