He hadn't wrestled since successfully defending the World Heavyweight Championship against Alberto Del Rio at WrestleMania XXVII in 2011.
The Rated-R Superstar abruptly retired, telling fans he was experiencing "numbness and uncontrollable trembling in his arms and hands." He met with a doctor who told him he needed to walk away and wouldn't be able to wrestle again.
Edge appeared at SummerSlam last August and delivered a spear to Elias.
Given his age (46) and injury history, a full-time comeback almost certainly isn't in the cards.
But PWInsider's Mike Johnson reported in December that Edge had signed a new deal with WWE. In addition to competing in the Rumble match, Johnson speculated Edge might "do a few matches on major events."
At the very least, seeing him back was a welcome surprise for fans Sunday.