Is Ganax, Astral Hunter legal in Standard, Modern, and Commander?

Ganax, Astral Hunter is legal in: Legacy, Vintage, Commander.

Ganax, Astral Hunter

Q: What type of card is Ganax, Astral Hunter?

Ganax, Astral Hunter is a Legendary Creature — Dragon. Its oracle text reads: "Flying Whenever Ganax or another Dragon you control enters, create a Treasure token. (It's an artifact with "{T}, Sacrifice this token: Add one mana of any color.") Choose a Background (You can have a Background as a second commander.)"

Legendary Creature — Dragon

Flying

Whenever Ganax or another Dragon you control enters, create a Treasure token. (It's an artifact with ", Sacrifice this token: Add one mana of any color.")