Is Walking Bulwark legal in Standard, Modern, and Commander?

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

Walking Bulwark

Q: What type of card is Walking Bulwark?

Walking Bulwark is an Artifact Creature — Golem. Its oracle text reads: "Defender {2}: Until end of turn, target creature with defender gains haste, can attack as though it didn't have defender, and assigns combat damage equal to its toughness rather than its power. Activate only as a sorcery."

Artifact Creature — Golem

Defender

: Until end of turn, target creature with defender gains haste, can attack as though it didn't have defender, and assigns combat damage equal to its toughness rather than its power. Activate only as a sorcery.