Last Post: 12:40:42pm, 12/15/2018
For South Park characters i'd say Randy Marsh should be on it as he's a dude.
IMO Essentials:
Cheetara and Liono from Thundercats
Optimus Prime and maybe Megatron too from Transformers
Buzz Lightyear and/or Woody from Toy Story
K.I.T.T from Knight Rider
Buffy the Vampire Slayer (SMG)
He-Man and Skeletor
Outsiders:
Mat Tracker from M.A.S.K
Jaws (the shark)
Peter Venkman from Ghostbusters
Michael Knight from Knight Rider
I think maybe Star Wars and Star Trek characters would be better off as part of an entirely different Sci-Fi set along with things like Terminator, Predator and Xenomorph.
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If you ran the world, it would probably be on fire right now.