As a card with the Bodyguard keyword, Minnie Mouse may enter play exerted, and must be the target of your opponents Challenge (or another character you have exerted with the Bodyguard keyword!)
This is something weve seen Sapphire specialise in a lot in the future, with cards like Gramma Tala, but it all started here with Mickey
In this case, well give it the benefit of the doubt since most of the storm combos in decks built around this card dont really need it to work properly, but still
Like other Extra Deck Monsters, Fusion Monsters cant be Special Summoned from the graveyard or from banishment unless they are successfully Fusion Summoned first unless an active card effect states otherwise
Legacy doesnt have room for many four-mana planeswalkers that dont end with the Mind Sculptor, and Kaya doesnt do anything against combo decks