If an effect needs to know what a player’s speed is and that player doesn’t have a speed, their speed is considered 0.
Mutant Surveyor
Your speed doesn’t change until a spell or ability says so, such as the inherent triggered ability that cares about opponents losing life during your turn. Notably, losing control of permanents with start your engines! doesn’t affect your speed.
Start your engines! isn’t a triggered ability. Increasing your speed to 1 is something that happens as a state-based action as soon as you control a permanent with the ability. Notably, this includes gaining control of a permanent with the ability that another player controls.
Magic: The Gathering · ™ & © Wizards of the Coast · Illus. Nicholas Gregory
Card data via Scryfall. Rarix is fan-made; not endorsed by the rights holders.
