Star-Reader Severin does a number of sweet things in this deck: he guarantees you have a unit to sac for gates without needing to pay extra mana, he gets huge off
Makkar's Quiver, and he makes opponents pause to read the card. He also perma-dies to Blightmoth but I think Blightmoth decks should be slow enough for this deck to combo kill even if he dies.
The combo kill in question is any relic weapon (Scythe if they have too many blockers to reasonably chop down),
The Nightmare Gates, and at least one
Jadehorn. If you only have one Jadehorn, you can Reweave it into another, then potentially even remembrance the first one to swing 3 times. Failing that, you can just make a giant relic weapon and beat em up.
Auric Reclaimer is a key card for the deck in case the first big weapon doesn't do the job,
Tax Collector is absolutely NOT a key card and do not craft it to play this deck, but once in a blue moon it makes me cackle like a madman at my huge relic weapon.