Optional effect

"Peten the Dark Clown", a card with an optional effect

Optional effects are effects that a player can choose whether or not to activate. Optional effects include the phrase "You can" in their card text.

Missing the timing

Main article: Missing the timing

Optional effects that use the word "When" can miss the timing. Optional effects that use other timing words, such as "If", cannot.

Mechanics

When multiple effects trigger at the same time, they are all placed on a Chain, with the mandatory effects being activated first, followed by the turn player's optional effects and then the non-turn player's optional effects.