Is Diamond Weapon legal in Standard, Modern, and Commander?

Diamond Weapon is legal in: Standard, Modern, Pioneer, Legacy, Vintage, Commander, Historic.

Diamond Weapon

Q: What type of card is Diamond Weapon?

Diamond Weapon is a Legendary Artifact Creature — Elemental. Its oracle text reads: "This spell costs {1} less to cast for each permanent card in your graveyard. Reach Immune — Prevent all combat damage that would be dealt to Diamond Weapon. *A tutelary creature said only to appear when the planet is in grave danger.* Power/Toughness: 8/8"