Smoke is a gray mustang and Spirit's rival for the role of protector of the herd of mustangs that ranges near Miradero. Smoke can be over-protective and aggressive, but sometimes is more bluster than follow-through.
Smoke challenged Spirit for control of his herd, and they fought each other at night time. Smoke tried to harm Lucky, but Spirit defended her. When Spirit joined Lucky in running away to join El Circo Dos Grillos, Spirit ceded his herd to Smoke.