18 Jan 2019 20 Jan 2019
There are two ways to unlock a Legendary skin:
1) Skins are awarded after each match played (in Arcade, Versus, or Matchmaking modes). There is a chance you'll get a Legendary skin during which the achievement will pop.
2) You can purchase a Legendary skin in the Garage for 2,000 coins. Coins are earned by being awarded duplicate skins after a match.