Whenever a team has a guy named "Prof" or "the Professor" on board, you know the rest of the group are bound to be a bit on the dim side. Professor Mark "Prof" Haley led the Challengers of the Unknown, and former prizefighter Rocky Davis was the dumbest of three dummies who followed him around, if only by virtue of his punch drunkenness. In Challengers of the Unknown #48, the team was checking in on and feeding their enemies, the League of Challenger-Haters, whom they were holding captive on a hidden island prison. When Rocky steps off the jet onto the barren, lifeless soil of the island, and sees a fluffy, white, cotton-tailed bunny rabbit looking up at him with it's bright eyes and twitching whiskers, he questions nothing, and sweeps the bunny up in a loving embrace. If this were any ordinary bunny, Rocky would pet it and stroke it and hug it until it stops moving, just like all his other soft pets; but brother, this is no ordinary bunny!
And so the Challengers of the Unknown were dead forever. No, not really. The Prof figured out that the "magic" compound that Multi-Man used to save Rocky earlier was a simple acid compound, found in powder form in Multi-Man's cell and applied liberally. Then they teamed up with the Doom Patrol in a crossover that continued into Doom Patrol #102.
By the way, that League of Challenger-Haters sure do hate the Challengers, don't they? What a zany bunch. Someone should do an article about them.