Challenger (Disney Lorcana keyword)
While this character is the one challenging, it gets +N Strength. It does nothing when the character is defending. Multiple instances add together.
Official rule 8.5 (Comprehensive Rules 2.2.0). This keyword appears on 43 cards: 43 Character. By ink: 23 Amethyst, 19 Steel, 1 Emerald.
All 43 cards with Challenger
See Challenger in the glossary