In the Cantina, there are yellow Stars beneath the Campaign's title representing the number of Stars earned when progressing through Light, Dark, Cantina, and Mod battles.

Each battle can grant up to 3 Stars, depending on how well the battle was fought. To see the number of stars earned per Campaign type, tap on the Campaign table and check the bottom section of each Campaign.

Missing Stars? Be sure to check both Normal and Hard mode for any incomplete battles.