Combo · ENGINE

Mageseeker Warden strands their face-down hidden units and Noxus Saboteur switches off the other hidden cards in the one combat where they would fire

2 cards · calm + fury · verified

Pieces

• Mageseeker Warden ×1 OGN-070 · enabler · calm

  While I'm at a battlefield, opponents can only play units to their base. While I'm at a battlefield, spells and abilities can't ready enemy units and gear.

• Noxus Saboteur ×1 OGN-018 · enabler · fury

  Your opponents' [Hidden] cards can't be revealed here.

Payoff

Deck

• Both bodies are cheap for what they do: 9 Energy and 1 Power for the pair, and the Saboteur adds his 3 Might to the attacking sum of 465.2.c rather than costing you a slot in the combat.

Run play

• The Warden keeps their battlefield small, and the Saboteur deletes one hidden card until a Gust

Prerequisites

• EXACTLY ONE LEGEND IN THE POOL ALLOWS THE PAIR. The Warden is Calm and the Saboteur is Fury; of the 49 legends only VEN-139 Rogue Assassin (Akali) is Fury/Calm, so 103.1.b.1 leaves no second shell. That is a hard prerequisite, not a preference.
• IT STANDS ON R33 = A, ruled 2026-09-06. Noxus Saboteur's 'can't be revealed here' forbids PLAYING the opponent's hidden card at that battlefield: 421.4 makes the reveal mandatory ('If a facedown card would change zones or if the game ends, its owner reveals it to all players'), 811.1.c.3 makes playing from facedown a zone change, and 054.1 makes the prohibition beat the permission 811.1.b grants. Reading B would leave the card dead letter, which is the argument this project already used for R28. A Riot ruling the other way collapses this entry to its Warden half.
• THE DIVISION OF LABOUR, MEASURED. The pool holds 39 [Hidden] cards - counted by the reminder text 'Hide now for', which is the keyword's real signature; a bare grep for the bracketed word gives 43 because four cards only mention it, the Saboteur among them. They are 22 spells, 15 units and 2 gear (OGN-077, SFD-139). The Warden stops a hidden unit that is already face down, at any battlefield, for as long as he stands at a battlefield (CORRECTED 2026-10-14, #365: this read 'kills the 15 units everywhere and permanently' - from hand they are played to base as normal, see step 1). The Saboteur kills the other 24, but only 'here' (359.3.f.1, 359.3.f.2: the referent is read from the source and checked on execution).
• WHERE 'HERE' HAS TO BE, AND WHY THAT IS THE POINT. 107.3.c - 'Cards can only be placed in or occupy the Facedown Zone if the controller of the card also controls the associated Battlefield' - means the opponent only has facedown cards at battlefields THEY control, so the Saboteur only bites standing on one, which is to say attacking. And the sequence favours it: you move him in a Neutral Open State of your Main Phase, where 312.2.a gives the opponent no priority at all; the Cleanup stages the Combat (323.9) and 323.13 opens it; 464 makes Step 1 the Combat Showdown, which by 312.2.b is the first moment they have Focus. He is already there when their window opens.
• SCOPE: ONE COMBAT, AND THE ENTRY SAYS SO RATHER THAN SELLING A LOCK IT CANNOT KEEP. 466.1.a.2 inserts '3d. Recall Attackers present at the Battlefield if Defenders are still present', so the Saboteur goes home the moment the garrison survives - and 455 puts a Recall at his base, where 'here' is no battlefield of theirs. If the garrison does NOT survive you take the battlefield, and then 107.3.d removes their facedown cards in the next Cleanup anyway. Either way this is a combat-scoped tool.
• What refutes it. The Warden is M5 with no [Deflect] (this read 'the Warden is M5 and the same', i.e. dies to anything, and is withdrawn with the Saboteur's half below). And 811.1.c.1 - 'Hide is not a subset of Play' - means the opponent may keep hiding cards under both of them: what is denied is playing the one already hidden, not the hiding. CORRECTED 2026-10-14 (#365, from the run play docs/plays/2026-10-14-the-warden-keeps-their-battlefield-small-and-the-saboteur-deletes-one-hidden-card-until-a-gust.md): this notable said the Saboteur 'dies to anything' and named nothing. Before he moves there is no window: 312.2.a gives the opponent priority only 'When the turn is in a Neutral Open State during their Main Phase', and 337.2 resolves a played unit immediately. On their turn he is in your base, out of reach of the 'a unit at a battlefield' spells. So the answer comes in the combat showdown. Of the 42 Mind/Chaos [Action]/[Reaction] spells in data/corpus_flat.txt (the two banned ones left out), the play counts four that break its T4 combat for one rune and five more for two. Two take him OFF the battlefield: OGN-169 Gust (Chaos, E1: 'Return a unit at a battlefield with 3 :rb_might: or less to its owner's hand.' - he is a 3) and OGN-172 Rebuke (Chaos, E2 P2: 'Return a unit at a battlefield to its owner's hand.'). With him gone 'here' is checked on execution (359.3.f.2) and the hidden card, which has [Reaction] while face down (811.6), is played at once. UNL-134 Existential Dread, VEN-052 Mesmerize and SFD-080 Bellows Breath leave him there and break the combat instead. Added beyond the lead: Existential Dread with its [Repeat] (E2 more, three runes in all) may choose him twice (820.2.a: 'Choices made for the additional execution do not have to be the same as the choices made for the initial execution.'), and 'If it's already stunned, return it to its owner's hand instead' then takes him off too. None of these is banned or in data/legality.src.json.
• THE FACEDOWN ZONE IS NOT A LOCATION, AND IT IS THE SAME SENTENCE THIS PROJECT USES ON THE LEGEND ZONE (#204, from #187 batch 19). 107.4.b - 'This is not a location' - is cited 26 times here and is what kills the whole legend-plus-Reckoner's-Arena family, because 'here' cannot reach a zone that is not a location. 107.3.e is the identical sentence for the Facedown Zone and was cited by nothing in 766 entries. Three uncited paragraphs finish the profile: 421.3 gives a facedown card no properties of its own except what the hiding effect grants, so it is not a unit, has no Might and no domain; 107.3.f makes the ZONE public while the CARD is private, which is why 'if you control a facedown card' is a legal thing for a card to read; and 421.4 reveals it to all players if it changes zones.
• THE WARDEN'S OTHER HALF IS THE ONE THAT PAYS - ADDED 2026-10-14 (#365, from the run play docs/plays/2026-10-14-the-warden-keeps-their-battlefield-small-and-the-saboteur-deletes-one-hidden-card-until-a-gust.md). With him at a battlefield no unit of theirs is played straight to a battlefield they control: 355.2.a's default ('the controller's Base or a Battlefield the controller controls') is cut to base by 054.2 ('If a card specifies that an action can "only" be performed under certain circumstances, it cannot be performed under any other circumstances.'), and 143.4 ('Units enter the Board exhausted.') means each new body reaches their battlefield a turn late. That turn of delay is the standard move's: its cost is exhausting the unit (144.2: 'Exhausting the Unit is the Cost for this action.'). Two leaks get round it. [Accelerate], 805.1.a: 'As you play me, you may pay [1][C] as an additional cost. If you do, I enter ready.' And any spell or ability that moves a friendly unit, since a spell move has no exhaust cost: OGN-173 Ride the Wind (Chaos, E2 P1: '[Action] (Play on your turn or in showdowns.) Move a friendly unit and ready it.') takes a body played to base this turn to their battlefield the same turn - the Warden's 'spells and abilities can't ready enemy units and gear' stops only the ready, so the body is there and defends a turn early. Others in the pool: VEN-105 Twilight Step (Chaos, 3 Might or less), UNL-202 Void Assault (Body/Chaos), SFD-184 Relentless Pursuit (Fury/Body), UNL-101 Call to Battle (Body, 'to a battlefield you control') and the OGN-259 Unforgiven legend ability. (CORRECTED in review, #365: the first draft named [Accelerate] as the only leak.)
• THEY SEE THE SABOTEUR FIRST - ADDED 2026-10-14 (#365, from the run play docs/plays/2026-10-14-the-warden-keeps-their-battlefield-small-and-the-saboteur-deletes-one-hidden-card-until-a-gust.md). He is played to your base, in public, a turn before he can attack, and 811.1.b lets them hide only on their own turn. A player who sees him keeps the trick in hand and plays it under 811.3 ('Instead of being hidden, a card with Hidden may be played for its cost as normal, at its normal timing with no restrictions on targeting.') at its printed cost. A card played from hand is never revealed from face down, so 'can't be revealed here' does not touch it.

Steps

1. Play the Mageseeker Warden to a battlefield (6 Energy + 1 Power). A [Hidden] unit of theirs that is ALREADY face down cannot be played while he stays at a battlefield: 811.1.d.1 needs it played to the battlefield it was hidden at, and 054.2 forbids it. CORRECTED 2026-10-14 (#365, from the run play docs/plays/2026-10-14-the-warden-keeps-their-battlefield-small-and-the-saboteur-deletes-one-hidden-card-until-a-gust.md): this step said their 15 [Hidden] units are 'unplayable for the rest of the game'. Only one already face down is, and only while the Warden is at a battlefield. From hand a hidden unit is played to base like any unit (811.3, quoted in 'THEY SEE THE SABOTEUR FIRST'), which the Warden allows. And in a Duel the face-down cards are few: 485.4 'Battlefield Count: 2', 107.3.b 'Each Facedown Zone has a maximum occupancy of one card.', and 107.3.c 'Cards can only be placed in or occupy the Facedown Zone if the controller of the card also controls the associated Battlefield.' - at most one per battlefield they control.
2. Play Noxus Saboteur to your base (3 Energy).
3. On a later turn, Standard Move him into the enemy battlefield that holds their facedown card (144.4.a). The opponent has no priority for this: 312.2.a gives it only in their own Main Phase.
4. At the Cleanup the Combat is staged (323.9) and opened (323.13). Step 1 is the Combat Showdown (464), the first window in which they could play the hidden card - and the Saboteur is standing there, so under R33 = A they cannot.
5. Resolve the combat with his 3 Might added to your summed assignment (465.2.c). If the garrison survives, 466.1.a.2 recalls him and the Saboteur half is over until you attack again.

How it ends

engine only - a hidden unit already face down stays stranded while the Warden stands at a battlefield, and the Saboteur's combat ends with the hidden card at that battlefield either removed or left where it was; nothing here scores. CORRECTED 2026-10-14 (#365, from the run play docs/plays/2026-10-14-the-warden-keeps-their-battlefield-small-and-the-saboteur-deletes-one-hidden-card-until-a-gust.md): this said 'the opponent's 15 hidden units never come off the table and the other 24 hidden cards are dead for the duration of one combat'. The first half is corrected in step 1. For the second: when the attack takes the battlefield, 466.5.c ('Remove all Hidden cards from this Battlefield that do not share a controller with the Battlefield.') removes the card unplayed, so the Saboteur's payoff is a deletion; when it does not, the recall (466.1.a.2 'Insert "3d. Recall Attackers present at the Battlefield if Defenders are still present."') leaves the card face down where it was.

Sources

Published elsewhere

• Denial lens hunt, issue #100 (rc-huntQ) 2026-09-06
• Riftbound Core Rules, Last Updated 2026-07-16 (data/Riftbound-Core-Rules-2026-07-16.txt) 2026-07-16

Walked here, in this project

• Hand walk 2026-09-06 2026-09-06 record

Walked against Core Rules 2026-07-16

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