Combo · ENGINE

Sprite Queen arms Shard of Undoing every turn instead of every other one, and Dusk Rose Lab charges the same scheduled death a card

3 cards · order + mind · verified

Pieces

• Shard of Undoing ×1 UNL-174 · payoff · order

  The first time a friendly unit dies during your Beginning Phase each turn, each opponent must kill one of their units.

• Sprite Queen ×1 UNL-084 · engine · mind

  When you play me or at the start of your Beginning Phase, play a ready 3 Might Sprite unit token with [Temporary] to your base. (Kill them at the start of their controller's next Beginning Phase, before scoring.)

• Dusk Rose Lab ×1 UNL-209 · battlefield

  At the start of your Beginning Phase, you may kill a unit you control here to draw 1. (This happens before scoring.)

Payoff

Deck

• Mind + Order: Sprite Queen is mono-Mind and Shard of Undoing mono-Order (103.1.b.3 admits each on its own), so the legend must hold both, and the pool prints exactly four names — OGN-265 Herald of the Arcane, OGS-021 Lady of Luminosity, SFD-201 Chem-Baroness and UNL-199 Deceiver. Dusk Rose Lab is colourless and constrains nothing.
• Dusk Rose Lab is one of your three battlefields. 485.4.a: a player provides three and only 1 is used; 485.5 makes that 1 random in a Duel. 103.4.c and Tournament Rules 402.1 forbid bringing two copies of a battlefield name, so there is no way to raise the odds.
• None of the three carries a [BANNED marker in data/corpus_flat.txt, and none is a Signature card, so no legend is forced by 103.2.d.2.

Run play

• the Lab is paid before anything resolves, and the Sprite it eats is the one Gust can reach

Prerequisites

• WHAT THIS BUYS OVER THE TWO SHARD ENTRIES ALREADY IN THE CATALOGUE, IN CARDS. sprite-fountain-shard-undoing-beginning-removal spends a Sprite Fountain (E2 + 1 Mind Power) per TWO turns — 'three Fountains played on a two-turn cadence cover six consecutive turns' — and shard-undoing-deceiver-reflection-removal spends a discard EVERY turn plus the legend's exhaust. Sprite Queen is ONE card that pays every turn for the rest of the game and costs nothing per turn; the Lab then adds a drawn card to the same death. Per-turn cost: zero cards, zero Energy, zero Power.
• THE SPRITE IS BORN READY AND HAS TO WALK. Sprite Queen plays it 'to your base', so it is at the base, not at the Lab. 143.4 ('Units enter the Board exhausted') is overridden by the token's own printed 'ready' — 143.4.a says outright 'This can be altered by Accelerate or similar game effects' — so it can pay 144.2's exhaust and take the Standard Move to the Lab (144.4: base to battlefield) in the very Main Phase it was born.
• THE SPRITE BORN THIS BEGINNING PHASE DOES NOT DIE THIS BEGINNING PHASE. 816.1.b is 'At the start of this permanent's controller's Beginning Phase, before scoring, kill this', and 816.1.c pins the Trigger Condition as 'the controller of the permanent's Beginning Phase starting' — the condition was already checked when the Sprite entered, so it survives the turn and dies at the START of the NEXT Beginning Phase. That is what makes the schedule a steady state: one Sprite dies and one is born in the same window, every turn.
• YOU ORDER THE THREE TRIGGERS, AND THE ORDER IS WHAT PAYS. At the start of your Beginning Phase three of your Triggered Abilities fire simultaneously: the Lab's 'you may kill a unit you control here', the standing Sprite's [Temporary] kill, and Sprite Queen's new Sprite. 383.3.d: 'If more than one Triggered Ability is Triggered simultaneously, then the player that controls the Abilities selects the order to place them on the Chain.' Put the Lab first: it eats the Sprite that 816.1.b was going to kill for nothing, and you draw 1. The [Temporary] trigger then finds its permanent already gone and does nothing.
• THE SHARD FIRES ONCE, WHICHEVER DEATH GETS THERE FIRST. 383.3.e.1: 'Such a Triggered Ability will only be performed the specified number of times each turn.' 'The first time a friendly unit dies during your Beginning Phase each turn' is one execution a turn, so the Lab route and the [Temporary] route are alternatives, not a doubling — which is exactly why the Lab is worth a card and not a second kill.
• THE OPPONENT PICKS WHICH OF THEIR UNITS DIES, AND [Deflect] NEVER CHARGES. 355.10.e: an object 'chosen in whole or in part by other players' is not a target, and its worked example is verbatim 'Each player kills a unit they control'. 809.1.c and 809.1.d charge only for spells and abilities that target or choose the Deflecting object. So the Shard is guaranteed, cheap removal of the opponent's WORST body — never of their best. Price it as attrition, not as an answer.
• KILLING YOUR ONLY BODY AT THE LAB HANDS THE LAB BACK, BEFORE YOU HOLD IT. Same finding as dusk-rose-lab-leblanc-beginning-draw, reached with a shorter chain because a Sprite has no Deathknell: the death makes a Cleanup Outstanding (319.6, 'After any number of Game Objects enter or leave the Board'), the Shard's trigger holds the state Neutral Closed (310.2) so 323.6's 'if the turn is in an Open State' is false at that Cleanup; the Shard resolves, the Chain empties, 319.5 makes another Cleanup, and THAT one is Neutral Open (310.1) and strips 'control of any controlled Battlefields without their Units occupying them'. 315.2.b.2 then Holds only what you still control. So the Sprite is never a garrison — it dies in that window whether the Lab eats it or not — and if you want the Lab's point you need a second body standing there. That is a deckbuilding choice, not a requirement of the line.
• BURN OUT IS THE ONLY CEILING ON THE DRAW. The Lab's card is a real draw, so 431.1.a applies: past the last card of the Main Deck the draw is a Burn Out and a point for the opponent (194.1.d). One card a turn on top of your Draw Phase is a two-cards-a-turn clock through a 39-card deck (103.2.a.1 puts the Chosen Champion in the Champion Zone before play), and the Lab's kill is a 'you may', so it can simply be declined once the deck is thin.
• THE LAB IS NOT LOAD-BEARING FOR THE KILL, AND IT COSTS THE ONE BATTLEFIELD SLOT (485.4.a). The Sprite carries [Temporary] and 816.1.b kills it "at the start of this permanent's controller's Beginning Phase, before scoring" on its own, already inside the Shard's window - so the forced kill runs with no battlefield at all. UNL-209 Dusk Rose Lab adds the "draw 1" on its optional kill and nothing else; read it as an upgrade, never as a requirement (noted by the #171 walk, 2026-09-07).

Steps

1. Bring Dusk Rose Lab as one of your three battlefields (485.4.a) and take control of it.
2. Play Shard of Undoing (E6) and Sprite Queen (E7 + 1 Mind Power). Sprite Queen's play trigger already gives you the first ready Sprite, at your base.
3. In that same Main Phase, Standard-Move the Sprite from your base to the Lab, paying its own exhaust (144.2, 144.4).
4. At the start of your next Beginning Phase three of your triggers fire at once. Order them with 383.3.d: the Lab's kill first.
5. The Lab kills the Sprite standing there; you draw 1. That death is the first friendly death of your Beginning Phase, so Shard of Undoing fires and each opponent must kill one of their own units (355.10.e — they choose).
6. Sprite Queen's other trigger resolves and a new ready Sprite appears at your base; 816.1.c keeps it alive through this turn.
7. Walk the new Sprite to the Lab in the Main Phase and repeat the whole schedule next turn, for no cards and no mana.

Per iteration

one forced enemy kill and one drawn card per turn, for zero cards, zero Energy and zero Power after setup

How it ends

engine only — one forced enemy kill in each of your Beginning Phases (capped at one by 383.3.e.1) and one card, unbounded in turns; the ceilings are Burn Out on the draw (431.1.a) and the fact that the opponent chooses their own casualty (355.10.e). Nothing here scores, and the Sprite standing at the Lab is never a Hold garrison.

Sources

Published elsewhere

• Riftbound Core Rules, Last Updated 2026-07-16 (data/Riftbound-Core-Rules-2026-07-16.txt) 2026-07-16
• Matrix families rows 19-47, second pass — issue #168 (GitHub) 2026-09-07

Walked here, in this project

• Hand walk 2026-09-07 2026-09-07 record

Walked against Core Rules 2026-07-16

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