Is Taniwha legal in Standard, Modern, and Commander?

Taniwha is legal in: Legacy, Vintage, Commander.

Taniwha

Q: What type of card is Taniwha?

Taniwha is a Legendary Creature — Serpent. Its oracle text reads: "TramplePhasing (This phases in or out before you untap during each of your untap steps. While it's phased out, it's treated as though it doesn't exist.)At the beginning of your upkeep, all lands you control phase out. (They phase in before you untap during your next untap step.)"

Legendary Creature — Serpent

Trample<br>Phasing (This phases in or out before you untap during each of your untap steps. While it's phased out, it's treated as though it doesn't exist.)<br>At the beginning of your upkeep, all lands you control phase out. (They phase in before you untap during your next untap step.)

Set Mirage

Rarity Rare

Artist Ian Miller