Holy-
I just noticed how smart the bots in coop are. For example, I was standing in very deep water with a Sonic and Tails bot, seeing if they'd be dumb enough to drown with me while I had an elemental shield. The Sonic bot quickly reacted a few seconds before the drown timer, turned around, and ran to a far spring ahead of me to get air. The Tails bot started to fly up to get some air as well; and even more mysteriously, they both came back and repeated the process over and over. Amazing in my opinion.
EDIT: I also noticed they collect rings. I went to Map 50 (Special Stage 1) and the Sonic bot did everything for me, all I had to do was guide it to the areas with rings.
EDIT2: They also kill badniks for me, but act strange toward Robotnik/Eggman.