Purphoros's Emissary is a common Enchantment Creature — Ox card from Pioneer Masters (PIO), collector number 152.
Bestow {6}{R} (If you cast this card for its bestow cost, it's an Aura spell with enchant creature. It becomes a creature again if it's not attached.) Menace (This creature can't be blocked except by two or more creatures.) Enchanted creature gets +3/+3 and has menace.