Is Colossal Skyturtle legal in Standard, Modern, and Commander?

Colossal Skyturtle is legal in: Modern, Pioneer, Legacy, Vintage, Commander, Historic.

What type of card is Colossal Skyturtle?

Colossal Skyturtle is an Enchantment Creature — Turtle. Its oracle text reads: "Flying, ward {2} Channel — {2}{G}, Discard this card: Return target card from your graveyard to your hand. Channel — {1}{U}, Discard this card: Return target creature to its owner's hand."