It should go without saying that the chance of finding a Pokmon holy grail card in your own collection is very slim, but if you dont check, youll never know
Then as your vehicles deal combat damage to your foes, you exile that many cards from their library and you can play them, although there is no mana-washing here, so in a mono-Blue deck you might find it rough to cast non-Blue, non-colorless cards
Unearth is probably just strictly worse than its closest cousins embalm, eternalize, and disturb because it usually only gives you back your creature temporarily
It's a 3-CMC (2 generic, 1 Green) enchantment that allows you to exile a creature you control to add X mana of any one color, where X is the creature's mana cost + 1
next, it can bounce a scary nonland permanent, so goodbye pesky planeswalker