Is Wandermare legal in Standard, Modern, and Commander?

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

Wandermare

Q: What type of card is Wandermare?

Wandermare is a Creature — Horse. Its oracle text reads: "Whenever you cast a creature spell that has an Adventure, put a +1/+1 counter on this creature. (It doesn't need to have gone on the adventure first.)"

Creature — Horse

Whenever you cast a creature spell that has an Adventure, put a +1/+1 counter on this creature. (It doesn't need to have gone on the adventure first.)

Set Throne of Eldraine

Rarity Uncommon

Mana Value 3

Artist Kari Christensen

Collector # 204

Scryfall Gatherer