There are three class challenges as part of The Menagerie. Warrior, Mage, and Hunter.
The Warrior Challenge puts you in against the third boss, Terestian Illhoof. You’re given a deck with some new cards in to play around with, and they make it easy to kill the 1/1’s with Whirlwind effects. It’s a fun boss, but only takes a couple of minutes to breeze through so don’t worry.
Hearthstone Card Fool’s Bane
The card reads: Unlimited attacks each turn. Can’t attack heroes.
This is a new weapon mechanic we have not see before exactly. This is an anti-aggro tool for sure, you will be able to clear up 4 small minion’s in one turn, pretty good.