Yeah I don't see the point in 4-star cards, I never use them in any situation because the 5-star cards completely outclass the 4 star cards in every way possible.

The only time 5-star cards are useless if you have to use low-stat cards to win certain types of card battles.

It would be nice if they removed the silly restriction on 4-star cards and allow us the use of one 4-star card.