Is Soulbright Seeker legal in Standard, Modern, and Commander?

Soulbright Seeker is legal in: Standard, Modern, Pioneer, Legacy, Vintage, Commander, Historic.

Soulbright Seeker

Q: What type of card is Soulbright Seeker?

Soulbright Seeker is a Creature — Elemental Sorcerer. Its oracle text reads: "As an additional cost to cast this spell, behold an Elemental or pay {2}. (To behold an Elemental, choose an Elemental you control or reveal an Elemental card from your hand.) {R}: Target creature you control gains trample until end of turn. If this is the third time this ability has resolved this turn, add {R}{R}{R}{R}."

Creature — Elemental Sorcerer

As an additional cost to cast this spell, behold an Elemental or pay . (To behold an Elemental, choose an Elemental you control or reveal an Elemental card from your hand.)