Card-Forge / forge

An unofficial rules engine for the world's greatest card game.
https://card-forge.github.io/forge/
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Exceptions for copying are not implemented completely #2222

Open tool4ever opened 1 year ago

tool4ever commented 1 year ago

707.9e. Some replacement effects that generate copy effects include an exception that's an additional effect rather than a modification of the affected object's characteristics. If another copy effect is applied to that object after applying the copy effect with that exception, the exception's effect doesn't happen.

Example: Altered Ego reads, "You may have Altered Ego enter the battlefield as a copy of any creature on the battlefield, except it enters with X additional +1/+1 counters on it." You choose for it to enter the battlefield as a copy of Clone, which reads "You may have Clone enter the battlefield as a copy of any creature on the battlefield," for which no creature was chosen as it entered the battlefield. If you then choose a creature to copy as you apply the replacement effect Altered Ego gains by copying Clone, Altered Ego's replacement effect won't cause it to enter the battlefield with any +1/+1 counters on it.

This one is bad because you could chain the copying to get infinite counters.

707.9f. Some exceptions to the copying process apply only if the copy is or has certain characteristics. To determine whether such an exception applies, consider what the resulting permanent's characteristics would be if the copy effect were applied without that exception, taking into account any other exceptions that effect includes.

Example: Moritte of the Frost says, in part, "You may have Moritte of the Frost enter the battlefield as a copy of a permanent you control, except it's legendary and snow in addition to its other types and, if it's a creature, it enters with two additional +1/+1 counters on it and it has changeling." Moritte of the Frost copies a land that has become a creature until end of turn. It would enter as a noncreature permanent, so it won't enter with two additional +1+1 counters on it and it won't have changeling, even if it becomes a creature later in the turn.

Wall of Stolen Identity:

707.9g. Some replacement effects that generate copy effects are linked to triggered abilities written in the same paragraph. (See rule 603.11.) If another copy effect is applied to that object after applying the copy effect with the linked triggered ability, the ability doesn't trigger.

github-actions[bot] commented 1 year ago

This issue has not been updated in a while and has now been marked as stale. Stale messages will be auto closed.

github-actions[bot] commented 1 year ago

This issue has not been updated in a while and has now been marked as stale. Stale messages will be auto closed.

Hanmac commented 1 year ago

Primal Clay and similar are this rule:

208.2b The card may have a static ability that creates a replacement effect that sets the creature’s power and toughness to one of a number of specific values as it enters the battlefield or is turned face up. (See rule 614, “Replacement Effects.”) Such an ability is worded “As [this creature] enters the battlefield . . . ,” “As [this creature] is turned face up . . . ,” or “[This creature] enters the battlefield as . . .” and lists two or more specific power and toughness values (and may also list additional characteristics). The characteristics chosen or determined with these effects affect the creature’s copiable values. (See rule 707.2.) While the card isn’t on the battlefield, its power and toughness are each considered to be 0.

and they should probably copy itself, but set the right PT values