Also has most combat experience and access to high-class gear.>Robin
That particular Robin is an all around failure, worst pick, for suicidals only>K.O.
Probably highest raw strength and combat ability, even counting Steven. But naive, dim and inexperienced.>Gumball
All you can count on is toonforce, also a habitual failure, probably second worst pick.>Marco
Broken with scissors, third worst pick without due to being second weakest after Gumball and only having some combat experience. (Yes, I know he punches monsters around, so do Finn and Robin and both are better at it).>Steven
Second best pick with hax (scissors trump spaceship), best without due to very high strength and durability, as well as a range of tanking and supporting abilities. Can keep you especially safe if you manage to fuse.