There are easy and difficult promotion events and you can follow
Rollbit Twitter to get notifications on time and have enough time to choose what events match you.
In the starting time I remember how Rollbit has the system of giving away daily rewards to the top in leaderboard who was Rollbit boss and get $5k daily but then they change the system and still they are distributing good rewards to players through different games and events.Twitter is good source to get updates about new promotions and giveaways from the team.