Loop

A loop describes a set of actions that could be repeated indefinitely during a game of Magic: The Gathering. 
==Description==
Loop are formed when the costs to perform each action is covered by one of the other components of the loop. Powerful loops produce something per rotation to be useful, such as:
*Infinite mana (<c>Zirda, the Dawnwaker</c> + <c>Grim Monolith</c>)
*Infinite tokens (<c>Midnight Guard</c> + <c>Presence of Gond</c>)
*Infinite life (<c>Archangel of Thune</c> + <c>Spike Feeder</c>)
*Infinite power (<c>Ceaseless Searblades</c> + <c>Wandering Fumarole</c>)
*Infinite damage or life loss (<c>Yawgmoth, Thran Physician</c> + two <c>Geralf's Messenger</c>)
*Infinite cards drawn (<c>Niv-Mizzet, the Firemind</c> + <c>Curiousity</c>)
*Infinite mill (<c>Painter's Servant</c> + <c>Grindstone</c>)
Things that are not usually useful without another combo piece:
*Infinite storm count
*Infinite entry, sacrifice, leaves or dies triggers (<c>Worldgorger Dragon</c> + <c>Animate Dead</c>)
*Infinite untaps (<c>Clever Conjurer</c> + <c>Forensic Researcher</c>)
*Infinite toughness (<c>Angelic Protector</c> + <c>Outrider en-Kor</c>)
Once a rotation is established it might be possible to take shortcuts. The rules for resolving loops are also defined under those for shortcuts.
Loops can't actually run infinitely. If the loop is possible due to the repeated actions of a player, the player must name an actual number of times they will continue the loop before stopping, usually a very large number. If the loop would be infinite due to mandatory actions, the game ends in a draw.
==Rules==
See: Shortcut
Category:Tournament rules