Lyonar swarm aims to flood the board with cheap, high-toughness minions and then turn them into threats with global pump spells. It goes under most other deck’s gameplans and can close games out quite quickly, while also being resilient against many popular forms of anti-swarm tech (i.e., damage-based AOE).

Core of the Deck

These are the cards which are at the heart of the archetype and present in any build.

The Golem Package

Metallurgist, Celebrant and Warblade offer cheap bodies and a pump effect. These cards are what make the deck tick and exemplify what the archetype is all about.

Tempo Removal

Alchemist, Draining Wave, Arclyte Sentinel, and Holy Immolation allow you to remove enemies while simultaneously building up your own board.

Others

Empyreal Congregation is the last major piece of the puzzle: when it hits three or more creatures, it is a very cost-efficient pump spell and instantly converts a board of random dorks into a scary clock for your opponent. Celerity makes Azurite Lion one of the best things to pump, while Spelljammer has high toughness and keeps the cards flowing.

Tech Choices

The version in the deck list presented above is very aggressive, all-in on dumping cards out of the action bar and building a huge board as fast as possible. If this version doesn’t suit your play style (or you find yourself running into too much dedicated hate on ladder), I’ve included replacement options that transform the deck into a slightly slower “anti-anti-swarm” build by emphasizing even higher toughnesses and unconditional card advantage.

Sunrise Cleric (→ Silverguard Squire)

Cleric is a well-statted 1-drop with a strong Opening Gambit. (Squire has… even more toughness! 3 to 4 is not a huge difference, but 5 toughness is a critical number for dodging much removal, and the Squire only needs 1 buff to get there.)

Fealty (→Trinity Oath)

Fealty is insane amounts of card advantage when played with any semblance of a board. It is the engine that drives the aggressive version, allowing you to play out your bar while keeping a healthy number of cards in hand.  (Trinity Oath is slower, but guaranteed to work in an emergency.)

Surgeforger (→Aurora and/or Silverguard Knight)

Surgeforger is the trickiest card in the deck to play correctly.  He’s fragile initially, so play him out of reach. Don’t play him at all unless you can immediately proc him, ideally at least twice. However, if he survives for a turn, he both becomes a huge beater himself and makes your whole board better. (Aurora is harder to remove but doesn’t leave behind value when it dies. Silverguard Knight really shines against general-based decks, locking them down so that the rest of your minions can whale on them.)

Other Options (Dreamgazer, Fighting Spirit)

If you find yourself not using the removal cards as much, substitute some of them out for Dreamgazer (has good synergy with Aurora if you choose to run it) and/or Fighting Spirit (which cantrips while offering a surprising relevant buff – one extra toughness on a Crestfallen allows it to lock down an enemy general for a whole additional turn.)