Battle Event is all about amazing rewards, which you get in exchange for gained Trophies.
Rewards can be claimed in exchange for:
  • Milestones - They change from event to event, but the things you can get tend to include things like Collection Scrolls, more Event Tickets, legendary item keys, legendary orb keys, and legendary event item keys. They provide some of the best gear in the game, so it’s totally worth your time. Currently, the best milestone reward is reached by gaining 20 million trophies.
    • Don’t worry about spending your trophies. When you craft a milestone, all Trophies used in the process are returned afterward, so you never actually lose a thing.
  • Ranking Rewards - you also gain rewards based on your ranking among other players. The total amount of trophies you collect is weighed against all other players. They consist of gems, legendary event equipment keys, and legendary orb keys.
    • Keep in mind: the numbers you see when you view the player rewards tab is constantly changing; you won’t stay in the top 10% if you get there, and then just quit for the rest of the event!
  • Guild Rewards - rewards for getting high scores in the event. Teamwork is key!