Erd: The Grim Triangle (Design Sketch)

Each player starts the game with 9 cards in their Reserve (rear-center pile):
  • 3 marked Heavy (cornervalue 2/3)
  • 3 marked Light (cornervalue 1)
  • 3 marked Decoy (cornervalue 0)
Heavy has the text "Value: 2 on Rush, 3 on Defense, 1 as a Turret"
Light has the text "After combat, recover one Light for each Heavy in your reserve."
Decoy has the text "Recover after combat"

Play is divided into rounds. At the start of each round, each player moves up to three cards, face down, from their Reserve into each of their Rush pile (front-right) and Defense pile (middle left). Then all piles are simultaneously revealed and combat happens.

When combat happens, if exactly one player's Rush pile has a higher total value than the opponent's Defense, that player wins the game. Otherwise...
...if both players have Rush piles with higher total values than the opponent's defense, whoever has the larger total of rush plus defense wins. If that's tied, whoever has the larger Rush pile wins. On an exact tie there, discard all Rush and Defense cards and the game continues. Otherwise...
...For every 3 points each player's Defense exceeds their opponent's Rush by, they convert one of their Defending Heavies (if any) into a Turret: they turn it sideways and leave it face up in their discard. All other cards in Rush and Defense piles, including Turrets, are discarded. (face-up sideways pile in the rear-right)

Then, recovery happens. Each player moves all their Decoys back to their Reserve. For each Heavy in their Reserve, they move a Light from their discard to their Reserve. (or all of them, if they kept more heavies than the Lights in their discard, but that's a stupid move.)

Finally, if all six Heavies are in the discard piles, an Escalation happens. If all Lights are in the discard, each player recovers one Heavy; otherwise, each player recovers a Heavy for each Light in their hand. Then, each player recovers all their Lights.

After checking for an Escalation, the next round begins.
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Patch 0.01
Functional changes
* There are now 6 decoy cards per player
* The decoy recovery rule is "recover decoys until you have 9 cards in reserve or there aren't any left."
* Players must put exactly 3 face-down cards in their Rush and Defense piles during double blind allocation
Reason: Removes cases where both players would wait for the opponent to commit to the number of cards in a pile before allocating their own.

Quality of Play changes
* Mercy Rule - if a player ends the round with no Heavies and at most one Light in Reserve, and no Escalation happens, they lose. (They're checkmated)
* Since a game can end on turn 1, it is recommended to play best-of-2N+1 matches for N>1.

(E) Note that the "they kept more heavies than the Lights in their discard, but that's a stupid move" play is now illegal as an emergent property.
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And, Q&A:
What was the process like for creating your game? How did the limitations influence your design?
Erd started as an intellectual response to a discussion with Keith about the Econ/Rush/Defense strategy triangle. The rules are mostly attempts to replicate the dynamics of a clash of RTS builds, but with very simple rules.

How do you think it turned out?
It didn't work as an 18 card game. Post-patch, it does ok but it's probably too simple and fast-paced for serious play.

Do you have future plans for this game?
Nope. I might drop it into the public domain.


New member
Patch 0.02
Functional changes
* New win condition: If, right before an Escalation, only one player has non-Decoys in Reserve, that player wins before Escalation.

Quality of Play changes
* Mercy Rule: Now applies when the loser has 0-2 Lights 0 Heavies in reserve vs. a Heavy in reserve.