Great card and at a great cost! It allows you to choose any deck and discard the top card which can mitigate the luck factor quite a bit! expert troll strategy: you can mill the deck of your partner
Guardián.
Interrupción: cuando Cosmo ataque o intervenga, nombra un tipo de carta y luego descarta la primera carta de un mazo. Si esa carta es del tipo nombrado, Cosmo no sufre Daño derivado (el Daño que figura debajo de INT o ATQ) con este uso.

Better than it seems at first glance.
If you can see what's in the top of a deck (Star-Lord, Jessica Drew, Heimdall...) You can ensure that he won't take any consequential damage.
Also... not 100% sure if that works, but if it does... just put him an Enraged in a Spider Woman deck and enjoy 3 attack without consequential damage.
I am confused by the phrasing "the deck". This doesn't tell me which deck it refers to. Is it the encounter deck, is it the player deck, or is it up to choice? filler, filler, filler, filler, filler, filler, filler, filler, filler, filler, filler, filler, filler, filler,