This allows you to keep pace and apply pressure through your army of creatures, but it wont win the game by itself
True, replaying the adventure again and again does give you lots of Y'shtola triggers, but it has me wondering whether there's a token subtheme to the deck, or if Hildibrand's ability is only meant to buff his own zombies
He is fairly pricey and doesn't do much to protect you against mass removal which is your biggest concern against slower decks
If you sacrifice it, you get to destroy an artifact, enchantment, or even proliferate, making it an excellent choice for counter-based decks
Vilis, Broker of Blood gives you the chance to draw a ton of cards, remove your opponents creatures, and even gain life