1) Each mission should get 3 "tiers". In each tier the mission should get harder with a better reward. for example tier 1 "Earn 250 XP in battles reward 100 crystals"" tier 2 " "Earn 500 XP in battles reward 200 crystals" Tier 3 "Earn 1000 XP in battles reward 600 crystals" Each day you get 3 mission with each one having 3 tiers. The first tier will give you mission chains, the rest are just for bonus rewards. At the end of the day (Server restart) any mission which has at least one completed tier gets replaced (or if all tiers completed, a new one). 2) Instead of mission chains going by day, it should go by amount of missions completed. for example, completing 14 missions (2 every day for a week) should give you the reward. Like if you think this should come to be! :)