Is Lochmere Serpent legal in Standard, Modern, and Commander?

Lochmere Serpent is legal in: Modern, Pioneer, Legacy, Vintage, Commander, Historic.

What type of card is Lochmere Serpent?

Lochmere Serpent is a Creature — Serpent. Its oracle text reads: "Flash {U}, Sacrifice an Island: This creature can't be blocked this turn. {B}, Sacrifice a Swamp: You gain 1 life and draw a card. {U}{B}: Exile five target cards from an opponent's graveyard. Return this card from your graveyard to your hand. Activate only as a sorcery."