Why Red: Floor is Lava, The Prank, Workout, Group Chat, etc.

Why TSC: Redstone Academy, Ultimate Minecart Race

Why Purple: AvM S3 (and why Red and TSC: Lush Caves, Night & Day)

This way everyone has a partner:

Blue Yellow

Red Green

TSC Animator

TCO TDL

Victim Mitsi

Purple King Orange