I HAAAAAAAAAATED THAT MISSION OMFG.Not always.
A second skulltula appears on every stage after you beat it, and they are way too annoying. For all of them, you have to play on hard mode with a certain character and weapon. Then you have to accomplish a certain task. If they weren't trolling you enough, they censor out some parts of the objective and have to guess what they are. It sucks.
I haven't played this since Smash Bros came out, but I think I had Link and Ghirahim at level 57, and the next highest was Lana at level 38, so a lot lower than my main 2. I have everyone at level 26 or higher just because. Not much else to say except that the mission to unlock the Level 3 Deku Spear is EVIL. YOU HAVE BEEN WARNED.