Zul’jin arguably looks like one of the worst cards in the deck.
The Lifedrinkers are just in there to fill the 4 mana slot and provide a bit of healing, as this deck lacks tempo you’ll need it.
Tundra Rhino acts as a Shaw and should theoretically synergize with the other beasts in the deck.
Rexxar is the wincon against control, playing Zul’Jin afterwards wouldn’t achieve much besides setting up lethal with a huge board of 3/3s and 2 animal companions.