Combo · ENGINE

Thwonk!'s [Repeat] is two stuns and two Eclipse Herald triggers — the opposite use of the same keyword

2 cards · calm · verified

Pieces

• Eclipse Herald ×1 OGN-059 · payoff · calm

  When you stun an enemy unit, ready me and give me +1 Might this turn.

• Thwonk! ×1 SFD-040 · engine · calm

  [Action] (Play on your turn or in showdowns.) [Repeat] 2 Energy (You may pay the additional cost to repeat this spell's effect.) Stun an attacking unit. (It doesn't deal combat damage this turn.)

Payoff

Deck

• Any legend with Calm among its two domains (103.1.b.3) — 16 names: Nine-Tailed Fox (OGN-255), Blind Monk (OGN-257), Unforgiven (OGN-259), Radiant Dawn (OGN-261), Wuju Bladesman - Starter (OGS-019), Fire Below the Mountain (SFD-189), Grandmaster at Arms (SFD-193), Blade Dancer (SFD-195), Emperor of the Sands (SFD-197), Bashful Bloom (UNL-189), Wuju Master (UNL-191), Gloomist (UNL-193), Green Father (UNL-195), Rogue Assassin (VEN-139), Curator of the Sands (VEN-145), Eye of Twilight (VEN-147).
• Four runes left ready through your own turn — E2 for the spell and E2 for the [Repeat] — because both are paid on the opponent's turn.
• The Herald standing as a defender where the attack lands; the +1s are only worth anything in a combat he is in.

Run play

• two stuns make the Herald nine, and all six attackers die

Prerequisites

• TWO EXECUTIONS, TWO SEPARATE STUNS, TWO SEPARATE TRIGGERS. 820.1.b: '[Repeat] is an optional cost that a player may pay to execute the effect of their spells and abilities a second time' — exactly one extra execution, no more. 820.2.a: 'Choices made for the additional execution do not have to be the same as the choices made' for the first, and 423.1.a.1 ('A Stunned Unit can not be Stunned again') forces you to use that permission: the second Thwonk! must pick a different attacking unit. Two stuns is two Eclipse Herald triggers, so +2 Might for the turn.
• THE WINDOW IS THE OPPONENT'S COMBAT, WHICH IS THE ONLY PLACE 'AN ATTACKING UNIT' EXISTS TO BE STUNNED. 464.2.c.3 hands out the Attacker designation inside a Combat, and 806.1.b lets an [Action] card be 'played or activated during Showdowns, even when it is not the Controlling player's turn'. So this is a defensive card, cast in the Combat Showdown the opponent's attack opens.
• WHAT THE STUNS ARE WORTH, PRECISELY. 423.1.b: 'A Stunned Unit does not contribute its might to damage in the combat damage step' — so two attackers are subtracted from 465.2.c's summed assignment. What they are NOT is removal: 423.1.c says a stunned unit 'must still have damage applied to it equal to, or greater than, its full might value to be killed', and 423.1.a.2 clears the status at step 3d of the end-of-turn cleanup. Nothing carries over to your turn.
• BOTH READIES ARE DEAD, AND THE ENTRY SAYS SO. 144.1.b forbids the Standard Move in a Closed State; 381 pins Activated Abilities to 'the Controlling Player's Turn and during an Open State' and the Herald has none anyway; and combat does not read exhaustion at all (464.2.c.3 designates by presence, 465.2.b sums Might). The payoff is the +2 Might, which 465.2.b/465.2.c read when the defending damage is assigned — the Herald defends at 9 instead of 7.
• The Energy is four runes held ready through your own turn, not four Energy from the pool: 167 empties every Rune Pool at the start of each player's Main Phase and 415.3.a readies your runes only in your own Awakening, so they are tapped at 164.2.a's Reaction speed on their turn.
• The contrasting entry on the same trigger card is eclipse-herald-existential-dread-repeat-bounce, where the [Repeat] is deliberately aimed at the SAME unit and therefore yields ONE Herald trigger and a bounce. Same keyword, opposite use, and the choice is 820.2.a's to make. vex-mocking-thwonk-wall runs this same spell under a different trigger card, where it relocates a [Tank] rather than growing a defender.

Steps

1. Have Eclipse Herald at a battlefield and four runes still ready when you pass the turn.
2. The opponent attacks; a Combat Showdown opens and 464.2.c.3 designates their attackers.
3. Tap four ready runes (164.2.a) and play Thwonk! for 2 Energy, paying its [Repeat] cost of 2 more (820.1.c.1).
4. First execution: stun one attacking unit. The Herald readies (dead here) and takes +1 Might this turn.
5. Second execution: 820.2.a lets you choose a different attacking unit, and 423.1.a.1 requires it. Stun that one; the Herald takes a second +1.
6. Combat damage: 423.1.b removes both stunned attackers from the attacking sum, while 465.2.b sums your defenders with the Herald at 9.

Per iteration

-1 card, -4 Energy, two attacking units contribute no combat damage, +2 Might on the Herald this turn

How it ends

engine — two attackers muted and a 9-Might defending Herald for one card and four Energy, three times a game (103.2.b); nothing here scores

Sources

Published elsewhere

• 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 2026-09-07, issue #169 — matrix families rows 6-18, second pass 2026-09-07 record

Walked against Core Rules 2026-07-16

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