I really like the card’s design and it’s one of the most fun cards to play yourself. It’s interesting to play different cards in every match and know what your opponent is about to draw.
It’s not always fun to play against it, though. Especially against very defensive wish decks that just remove everything you play, then outvalue you with the cards drawn from wishes. If the opponent efficiently maintains board control, then plays Three Wishes, there’s basically no way you can win anymore. It just becomes a long, drawn out match that’s boring for the player that isn’t playing wishes.
There’s a bit too much variance in how useful Three Wishes can be. At best, it can give you cards that allow you to play overpowered strategies, like playing 6 cheap Soul Eaters in one turn. At worst, it’ll give you three cards that aren’t useful at all for the rest of the match. Randomness plays too big of a role there, especially since it’s a card that decks rely on to win the match.
Three Wishes is interesting in that it encouraged a lot of new decks to be created. However, the vast majority aren’t really four color decks. Almost all wish decks are just 2 colors, wishes and earthcraft. So they’re essentially just two color decks with a few extra cards.
There are only a few decent tri color decks and no four color decks, as far as I know. The four color fairy deck is fun, but it’s pretty weak.
It’s a shame true four color decks don’t really work. I’ve tried using them, but you end up getting too few good cards to play early on, which causes the decks to work too inconsistently. Even tri color decks only barely work, since it takes quite long before you can make enough lands to play all three colored cards.
Three Wishes is better balanced since the last balance patch. It doesn’t feel like it automatically allows you to make a comeback anymore, since the faeria cost adds some risk to using it. It still might be a bit too powerful, though. The discounted cards are a huge advantage, since you can do the same thing your opponent is about to do, but more efficiently.