43

In general, your opponent cannot conclusively verify that your deck is legal. As you mention, you can always concede to prevent them from seeing certain cards. However, this statement that you made in your question is incorrect: since one can never prove that I'm cheating, one can't call a judge either Players can call a judge for any number of reasons, ...


16

The key phrase in that rule is in the first sentence: A player uses or offers to use a method that is not part of the current game (including actions not legal in the current game) to determine the outcome of a game or match. Importantly, it is not a violation of this rule to take an action that is legal in the current game to determine a winner. For ...


15

Presenting a card as your companion requires you meet the companion condition. Like every keyword in magic, there is a section of the comprehensive rules that cover the ability, and those rules are what really matter. I think what you're doing is reading the reminder text as if it were the entirety of the rules for companion (reminding that you can cast a ...


14

This situation, in which no player knows whether a sequence of mandatory actions will end or loop forever, is so rare and so niche that neither the comprehensive rules nor the tournament rules address it. By a strict reading of the rules, players would need to continue executing the loop until they either know it will end, or that it will loop forever. ...


12

The assumption is people are playing with legal decks - this is enforced at higher rules level events by random deck checks (where players are randomly selected and their decks compared to the decklist they submitted) and being able to call a judge when you find that your opponent's deck is not legal for whatever reason (including a 5th copy of a card) ...


7

Companion-related cheating is much the same as other existing forms of cheating regarding illegal decks and sideboard. Call a judge just like in any other situation where you suspect someone is running an illegal deck. The updated Infraction Procedure Guide (IPG) has specifically addressed Companion cards. At a high level, Companion deck restrictions fall ...


6

The tournament rules only allow official WotC product and make no distinction between basic lands and others. What would actually happen in a sanctioned event is ultimately the decision of the head judge, as there is no explicit penalty for using counterfeit cards that are indistinguishable from real cards. From the MtG tournament rules, section 3.3 "...


4

According to the rules, the machine would be played out until one of the following occurs: It halts. (A player wins and the other loses) It visits a previously-visited state. (Loop of mandatory actions ⇒ Draw) Time runs out. (Draw) Of course, tournaments have human judges and human organizers, and these may decide a different outcome is appropriate. ...


3

A player may declare a companion only if that player's starting deck conforms to that companion's deckbuilding rule. You cannot directly check your opponent's deck for being legal for that companion; only a judge may perform a deck check. You assume the opponent follows all rules until you see they don't; in that case, you call a judge. That being said, ...


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