Aluren in Premodern: the free-creature enchantment and the Cavern Harpy loop that wins on the spot

What it does

Aluren is a four-mana green enchantment: any player may cast creature spells with converted mana cost three or less without paying their mana cost. The symmetry is real — both players can play free creatures — but the Aluren archetype exploits the effect first and wins immediately. By building a deck that can win with free creatures (specifically Cavern Harpy + Parasitic Strix or similar loops), the Aluren player resolves the enchantment and then immediately assembles the win condition, before the opponent can exploit the symmetry.

When it’s played

Aluren is the namesake card of the Aluren archetype — a combo deck designed to resolve the enchantment and win in one turn.

The Aluren deck uses Wall of Roots and Dark Ritual for acceleration, Brainstorm and Impulse for filtering, and Cabal Therapy for disruption. The combo requires Aluren in play plus Cavern Harpy (bounce itself back to hand for one life) plus Parasitic Strix (drain one life when it enters under Aluren’s condition) — repeatedly bouncing Harpy and replaying Strix drains the opponent to zero.

The math / interaction worth knowing

The Aluren-Cavern Harpy-Parasitic Strix loop. With Aluren in play: (1) Cast Cavern Harpy for free (CMC 2). (2) Cavern Harpy enters; if another Harpy is in play, bounce one back to hand. Actually: Cavern Harpy’s ability says “when Cavern Harpy enters the battlefield, return a blue or black creature you control to its owner’s hand.” This can return itself. Wait — Harpy can only return a creature you control that is blue or black; Harpy is both blue and black. So it can bounce itself. But if you bounce itself the turn it enters, it went to the battlefield and immediately returned. With Aluren, you cast it again for free and it re-enters. Each re-entry triggers the Harpy’s ability — but you need a second creature (like Parasitic Strix) to drain life or gain value each loop. The specific combo:

With Aluren + Cavern Harpy in hand + Parasitic Strix in hand (or wherever):

• Cast Parasitic Strix for free. It enters and drains 2 life from opponent.
• Cavern Harpy enters: bounce a blue or black creature — bounce Parasitic Strix.
• Cast Parasitic Strix again for free. Drain 2 more.
• Continue bouncing Strix and re-casting it until opponent is at zero.

The Cavern Harpy costs one life each loop (its “return to hand” ability has a life cost?). No: checking Cavern Harpy’s actual text — “when Cavern Harpy enters the battlefield, return a blue or black creature you control to its owner’s hand. Pay 1 life: return Cavern Harpy to its owner’s hand.” The life cost is on the second ability, not the first. So the loop works freely.

Disrupting Aluren before it resolves is the primary defense. Counterspell on Aluren preempts the entire combo. The Aluren pilot must have protection — Cabal Therapy to strip the counter before casting Aluren, or Brainstorm to reload after a counter.

Decklists worth studying

When deck data populates, look for Aluren combo lists from MTGO Premodern Challenges. The deck is four colors (WUBG in some builds) and the combo is compact — finding the right creature density alongside disruption is the build challenge.

Related cards

• Wall of Roots — The accelerant that enables turn-three Aluren.
• Cavern Harpy — The free bounce engine that enables repeated creature re-entries under Aluren.
• Cabal Therapy — Strips the opponent’s counterspell before Aluren is cast.
• Brainstorm — Filters toward the combo pieces and finds disruption.
• City of Brass — Mana base support for the four-color configuration.
• Dark Ritual — Alternative acceleration in black-splash builds.