Magmaquake doesn't target any creature or planeswalker. For example, it will deal damage to a creature without flying that has hexproof.
Legalitet:
Standard: Ej legal
Pioneer: Ej legal
Modern: Legal
Legacy: Legal
Vintage: Legal
EDH / Commander: Legal
Pauper: Ej legal
Explorer: Ej legal
Historic: Legal
Brawl: Ej legal
Premodern: Ej legal
93/94: Ej legal