What Skadi said, @Skadi - focus on your first 6 star champ. Kael will carry you as your strongest champ and best farmer for many months to come most likely, until your at a point where you've accumulated several 6 stars and many epics/legos. Focus on using all of your rare books on Kael and maxing out all his skills. He will be a monster once you fully max him, it was a game changer for me. Your second best hero is probably Ninja, atleast for clan boss. His Ascension lv. 3 Escalate ability does a number on CB. And for CB especially, you want to keep your champs' alive aslong as possible. For me, I use 2-3 Attack based heros with lifesteal gear, (remember, the % of healing from lifesteal is proportional to the amount of damage you deal, in other words, you want lifesteal on your strongest ATK based heros.) a support hero with healing abilities/ ally protection, and for the 5th spot usually a void hero that is DEF based. What people call your "Tank". If you want to deal damage and stay alive in CB and Dungeons like Spider and Fire Knight, put lifesteal on a maxxed out Kael, with another gear set like Cruel or Offense, and always have one or two heros on the team that hit the enemy with debuffs like decrease defense, so your nukers can step in and deal even more damage. DEF or HP based heros that can stay alive for a long time and aren't built around Attack are your best bet when it comes to debuffers and healers.