True Believer: 35,000 Studs
(1) Charge up an electro port in the stands stage left.
This ejects a minikit.
(2) Use magic to unfurl the five rolled banners around the stadium railing. They all look the same and are on the same level- none hidden in the stands or the stadium itself. Unroll all five for minikit.
(3) Time-warp a flower in the extreme downstage right corner, and use it as trampoline to grab another minikit.
(4) Timewarp the same flower back to a pile of dirt, and dig it up for yet another.
(5) Blast away the silver support legs of a fire-pot upstage right.
Douse the flaming wreckage with shield or beam, and assemble the pieces for a minikit.
(6) During the fight, you have to activate a shield-receptor downstage left, and a guy drags a gold-chariot out of the wall.
Enter the tunnel he came out of to find a minikit.
(7) Blast apart the five skeletons wearing silver armor. Four are scattered about the arena floor, one is in the stands stage right.
(8) Pull the loops handles in the loop-handled wreckage upstage left to reveal a minikit.
(9) Blast apart the gold chest behind the throne of the Red King himself, who's remarkably chill about the whole thing.
(10) Just right of the Red King's stand, levitate the giant burger to reveal a grav booster inside.
Activate it with a grav bomb to blow up a nearby cage, releasing the final 'kit.
Hidden Character: Beta Ray Bill
Follow a clue trail by the downstage-left spike pit.
Dig up the dirtpile at trail's end to uncover a magic rake. Levitate it to clear the nearby trackball console.
Use a ball-form character in the console to retract the nearby spikes, clearing the card for pickup.
Stan Lee: Stan is being menaced by some toughs in the stands just left of the Red King's minitower (Stan himself may be hidden by the giant torch there). Beat up the toughs to free the man.
Completing all of the above completes the level.