Historical Rules · 7 June 2024
Rule 702.116a
Official source text from the 7 June 2024 Rules release
Myriad is a triggered ability that may also create a delayed triggered ability. “Myriad” means “Whenever this creature attacks, for each opponent other than defending player, you may create a token that’s a copy of this creature that’s tapped and attacking that player or a planeswalker they control. If one or more tokens are created this way, exile the tokens at end of combat.”