Is Mycosynth Golem legal in Standard, Modern, and Commander?

Mycosynth Golem is legal in: Modern, Legacy, Vintage, Commander.

Mycosynth Golem

Q: What type of card is Mycosynth Golem?

Mycosynth Golem is an Artifact Creature — Golem. Its oracle text reads: "Affinity for artifacts (This spell costs {1} less to cast for each artifact you control.) Artifact creature spells you cast have affinity for artifacts. (They cost {1} less to cast for each artifact you control.)"