Concept

Saberspine Tiger + Abhorrent Unbirth is a 7-mana combo that converts your entire board into rush face damage. This little package can slot into a few different decks to provide a backup combo finisher to complement the main gameplan, like Dying Wish (in which you can drop discounted minions to boost damage on the combo turn), Swarm (which can quickly assemble large amounts of power on board), or Xor (which has its own synergies with sacrifice effects and Tiger). The build presented here is a more all-in combo version, with additional rush units supporting Unbirth as the primary finisher.

Cards

Unbirth

Your primary wincon is the Unbirth combo. This means you want to play a little defensively, in order to have plenty of Abomination food, and be aware at all times of how close you are to having a lethal Abomination. The surprise factor is real, as opponents will usually not know what’s coming and may make suboptimal plays as a result.

Rush minions – Tiger and Metaltooth

These have only two health, and hence can’t be counted on to survive a turn on the board. This means that you will almost always need 7 mana to combo, through either Tiger + Unbirth or Metaltooth + another 2-mana mech + Unbirth. Having six of these means you shouldn’t be shy to use a couple as removal early if necessary.

Value minions – Replicant, Operant, P. Fist, Sentinels, Priestess, Reaper

The rest of your minions are there to get you to the lategame and then provide beef up the Abomination. Hence, we need sticky minions, card advantage, and strong stats to cost ratios. The mechs are necessary to support the Rush on Metaltooth. Primus Fist helps with trades early and leaves a good body behind. The Sentinels provide card advantage in the form of overstatted cheap minions, which synergise excellently with Unbirth. Priestess pumps out a lot of bodies. Reaper is sticky and provides huge tempo swings if you can follow one up with a Chakram.

Boosts – Chakram and Void Steal

Chakram is great in any minion-based deck, but in particular, here turns your Rush minions into Flashed Makantors. If you can keep one intact, it makes assembling lethal much easier due to how it both buffs your board before it’s sacrificed to Unbirth and then also buffs the Abomination itself. In any case, even if your opponent does manage to break it, having to aim direct damage at your face often means that your minions are left alive. Void Steal does everything this deck needs – neutralizing an enemy while providing a permanent attack buff contributes a lot to helping your board survive and can even win the game by itself if you get some good positioning. It’s usually still a good idea to kill the debuffed minion, though, in order to avoid any unpleasant surprises.

Removal – Lure, Banishing

Lure is an Abyssian staple and their best-tempo removal. Banishing does subtract from your board but I feel that having a little hard removal is nice in the meta right now.

Upgrades

There are a few legendaries that would slot in naturally. Letigress provides another source of rush and is a solid value generator in her own right. Some other potential value creatures are Desolator (shores up some of the weak points of the deck by providing healing and general ping, along with more card advantage) and Kron (good stats spread over multiple bodies, and can even provide rush sometimes for Hail Mary lethals).

If you’re looking for an overall better deck that still incorporates the Unbirth package, I would recommend the Dying Wish build mentioned in the intro (like DeathsAdvocate’s take here).