Is Herald of Leshrac legal in Standard, Modern, and Commander?

Herald of Leshrac is legal in: Modern, Legacy, Vintage, Commander.

Herald of Leshrac

Q: What type of card is Herald of Leshrac?

Herald of Leshrac is a Creature — Avatar. Its oracle text reads: "Flying Cumulative upkeep—Gain control of a land you don't control. (At the beginning of your upkeep, put an age counter on this permanent, then sacrifice it unless you pay its upkeep cost for each age counter on it.) This creature gets +1/+1 for each land you control but don't own. When this creature leaves the battlefield, each player gains control of each land they own that you control."

Creature — Avatar

Flying

Cumulative upkeep—Gain control of a land you don't control. (At the beginning of your upkeep, put an age counter on this permanent, then sacrifice it unless you pay its upkeep cost for each age counter on it.)

This creature gets +1/+1 for each land you control but don't own.

When this creature leaves the battlefield, each player gains control of each land they own that you control.

Set Coldsnap

Rarity Rare

Mana Value 7

Artist Alex Horley-Orlandelli

Collector # 62

Scryfall Gatherer