Is Smelted Chargebug legal in Standard, Modern, and Commander?

Smelted Chargebug is legal in: Modern, Legacy, Vintage, Commander, Pauper, Historic.

What type of card is Smelted Chargebug?

Smelted Chargebug is an Artifact Creature — Insect. Its oracle text reads: "Menace When this creature enters, you get {E}{E} (two energy counters). Whenever this creature attacks, you may pay {E}. If you do, another target attacking creature gets +1/+0 and gains menace until end of turn."