Please keep the forum protocol in mind when posting.

Competitive REL » Post: Intentionally causing infinite loops

Intentionally causing infinite loops

July 27, 2013 11:57:06 PM

Chris Lansdell
Judge (Uncertified), Scorekeeper

Canada - Eastern Provinces

Intentionally causing infinite loops

Hey judges,

This came up today at GP Calgary while throwing scenarios around. Player A controls Life and Limb and Sporemound. Player N controls Lightning Angel. A is at 3 life and has 2 Forests in hand. Seeing he cannot win, he plays his Forest and says “it's a loop, the game is a draw. Next game?” In game 2, the same situation occurs: A cannot prevent himself from taking lethal damage on N's turn, so plays a land and causes a loop.

Is there an infraction here? If so, what is it? If not, would your answer change if he also controls Greater Good?

Sporemound
Creature — Fungus 3/3, 3GG (5)
Whenever a land enters the battlefield under your control, put a 1/1 green Saproling creature token onto the battlefield.

Life and Limb
Enchantment, 3G (4)
All Forests and all Saprolings are 1/1 green Saproling creatures and Forest lands in addition to their other types.

Greater Good
Enchantment, 2GG (4)
Sacrifice a creature: Draw cards equal to the sacrificed creature's power, then discard three cards.

July 28, 2013 12:25:41 AM

Cris Plyler
Judge (Level 2 (Judge Academy))

USA - Great Lakes

Intentionally causing infinite loops

There would not be an infraction here. Even though this may seem a bit unfair, there is no rule against it. A player is allowed to start a loop of mandatory actions that neither player can interupt, thus having the game end in a draw.

Edit - Really it isn't unfair, the player is just using a strategy to end the game to move on to the next game. It would be no different if the player could find a way to deal lethal damage during their turn to their opponent, when the opponent would have had lethal damage next turn.

Edited Cris Plyler (July 28, 2013 12:27:54 AM)

Aug. 1, 2013 12:32:01 AM

Stephen Hagan
Judge (Level 2 (Judge Academy)), Scorekeeper

USA - Great Lakes

Intentionally causing infinite loops

Ok, is it late and I am not thinking? What is the loop?. What am I missing?

Edited Stephen Hagan (Aug. 1, 2013 12:32:33 AM)

Aug. 1, 2013 12:48:42 AM

Paul Baranay
Forum Moderator
Judge (Level 5 (Judge Foundry))

USA - Northeast

Intentionally causing infinite loops

Life and Limb makes each Saproling into a Land Creature - Saproling Forest. As a result, playing a single land will result in Sporemound triggering, making a Saproling…which is also a land, so Sporemound triggers again…and again…and again. We end up with a loop of mandatory actions that draws the game:

716.4. If a loop contains only mandatory actions, the game is a draw.

(EDIT: formatting.)

Edited Paul Baranay (Aug. 1, 2013 12:48:58 AM)

Aug. 1, 2013 12:49:35 AM

Cris Plyler
Judge (Level 2 (Judge Academy))

USA - Great Lakes

Intentionally causing infinite loops

Originally posted by Stephen Hagan:

Ok, is it late and I am not thinking? What is the loop?. What am I missing?
Whenever sporemound makes a saporling token it's also a forest, so it triggers sporemound again….and again….and again…

Aug. 1, 2013 12:50:10 AM

Rebecca Lawrence
Judge (Uncertified)

USA - Midatlantic

Intentionally causing infinite loops

Sporemound has a mandatory trigger that occurs when a land ETB under your control; Life and Limb makes it so that any Forest or Saproling you control is also a land. So play a basic Forest, or make a Saproling, and you start an infinite sequence of events that can't be directly halted because of the mandatory triggers that will then occur infinitely.

Aug. 1, 2013 08:58:17 PM

Michael McGee
Judge (Level 1 (Judge Academy)), Scorekeeper

USA - Northeast

Intentionally causing infinite loops

He would be required at some point to use the Greater Good I would say to stop the loop if the action is possible. I am not quite sure on this part but I think so.

Aug. 1, 2013 09:11:45 PM

Josh Stansfield
Judge (Level 2 (Judge Foundry))

USA - Pacific West

Intentionally causing infinite loops

No, that's explicitly not required, since Greater Good is not part of the loop of mandatory actions.

716.5. No player can be forced to perform an action that would end a loop other than actions called for by objects involved in the loop.
Example: A player controls Seal of Cleansing, an enchantment that reads, “Sacrifice Seal of Cleansing: Destroy target artifact or enchantment.” A mandatory loop that involves an artifact begins. The player is not forced to sacrifice Seal of Cleansing to destroy the artifact and end the loop.

Edited Josh Stansfield (Aug. 1, 2013 09:12:08 PM)

Aug. 1, 2013 09:12:20 PM

Paul Baranay
Forum Moderator
Judge (Level 5 (Judge Foundry))

USA - Northeast

Intentionally causing infinite loops

Actually, the Comp Rules explain that this is not the case. Greater Good doesn't impact this scenario at all.

Originally posted by Comprehensive Rules:

716.5. No player can be forced to perform an action that would end a loop other than actions called for by objects involved in the loop.

Example: A player controls Seal of Cleansing, an enchantment that reads, “Sacrifice Seal of Cleansing: Destroy target artifact or enchantment.” A mandatory loop that involves an artifact begins. The player is not forced to sacrifice Seal of Cleansing to destroy the artifact and end the loop.

(EDIT: Nath'd by bimmer.)

Edited Paul Baranay (Aug. 1, 2013 09:12:39 PM)

Aug. 1, 2013 09:13:46 PM

Bryan Prillaman
Judge (Level 5 (Judge Foundry))

USA - Southeast

Intentionally causing infinite loops

Echoing what Josh said, but the rules text is a little odd, and people don't always understand it. Fortunately it has an example:

Example: A player controls Seal of Cleansing, an enchantment that reads, “Sacrifice Seal of Cleansing: Destroy target artifact or enchantment.” A mandatory loop that involves an artifact begins. The player is not forced to sacrifice Seal of Cleansing to destroy the artifact and end the loop.