Don’t invest heavily into your Common and Uncommon Champions early in the game.In addition, that Champion might be useful for a particular challenge you’ll find yourself struggling at some point. Reason being, it’s difficult to get Void, Epics and Legendaries every day. Don’t ever sacrifice your Void, Epic and Legendary champions unless there’s really a good reason for it such as leveling up Skills on a Champion you have duplicates of.
Buy all Uncommon and Common Champions from Market and use them as fodder instead of using Mystery Shards to save them for Champion Fusion Event.You will need at least 1600 Mystery Shards to get the required champion for Champion Fusion event. Buy all the Mystery Shards from Market and save them for Champion Chase Tournament.