Is Tinybones, Bauble Burglar legal in Standard, Modern, and Commander?

Tinybones, Bauble Burglar is legal in: Standard, Modern, Pioneer, Legacy, Vintage, Commander, Historic.

Tinybones, Bauble Burglar

Q: What type of card is Tinybones, Bauble Burglar?

Tinybones, Bauble Burglar is a Legendary Creature — Skeleton Rogue. Its oracle text reads: "Whenever an opponent discards a card, exile it from their graveyard with a stash counter on it. During your turn, you may play cards you don't own with stash counters on them from exile, and mana of any type can be spent to cast those spells. {3}{B}, {T}: Each opponent discards a card. Activate only as a sorcery."