With Flex - we have made challenging anyone super FLEX-ible. There are 3 ways to challenge someone on flex.
Direct Challenge - This is a 1:1 Challenge with a team you have access to - like your leaguemates, you can create a challenge with anyones’ team from the leagues you're associated with.
Open Challenge - This allows the entire Flex Community to challenge you. You place your team in the Arena page and other teams will submit to play you. You then pick the team you’d like to play against and kick off the challenge.
1-Click Challenge - Anyone you see on flex can be challenged or rechallenged. Simply look for the 1-click challenge button (logo), with your defaults set, and you’ll launch right into a confirmation to challenge that user. See someone on the leaderboard ahead of you? Challenge them. Finish a game but want an exact rematch? Choose a 1-click challenge on the matchup page..