41: Its on temple, so go down the bottom of the stage and edgeguard.
42: Throw bowser off the side of squirtles head.
43: Shine a lot.
44: Avoid Zelda like it says. Mewtwo appears on the left platform at the 15 second mark. Use this knowledge to get first damage.
45: Up-B
46: Use your best character.
47: Use your best character again, reset until you get the three Cpus you find easiest to fight.
48: Use a fast character that can easily chase the pichus and avoid pikachu.
49: Use your best character again. That's really your best option for almost every event that lets you choose your character.
50: Attack crazy hand when one of the hands is doing their laser attack.
51. Use jigglypuff and press down-b a lot. Alternatively, use your best character.
I'd wait for another reply though because there's probably better strategies than these.