(When a creature with undying dies, if it had no +1/+1 counters on it, return it to the battlefield under its owner's control with a +1/+1 counter on it.) Whenever a Human deals damage to you, destroy it
In a control deck, this allows you a lot of versatility and gets a body on the field for blocks
Fabricate creatures let you make a choice when you play them: you can either opt to beef up their base stats, or they can bring along some mechanised friends for the ride
Ultima Ultima does three big and impactful effects in one card
Instead, look for build-around cards like Dread Presence, Empyrean Eagle, Gnarlback Rhino, or cards with traits you know you'll use like removal and cheap ramp (examples: Chandra's Outrage, or Leafkin Druid)