The problem is charge minions. Face Hunter wouldn't be very effective without Wolf Rider, Huffer, Arcane Golem, and Leeroy Jenkins. It's the same issue with Druid too. If you get below 14 life against a Druid and don't have a taunt on board, hold your breath. Warrior too with Grommash and 10 to 12 life. There needs to be a minion like Ancient Watcher that can't attack, but prevents minions from charging while it remains on the board.