I personally would use the team of Pumpkin Duke, Immortep, Santa, Harpy Queen, Druid then add in Thunder God but also keep orksbane leveled as well because of his use in lost realm, lost battle field, mesa and guild boss fight. If you choose to level orksbane as well then say level 120 and 4/10 skill will do fine for now.
Pumpkin Duke to 7/10 then 8/10 when you can manage it. Reasoning is he is important for all game modes including boss fight that will help fund you leveling your heroes.
Immortep's skill is fine where it is
Santa Boom to 6/10 skill atleast. After pumpkin duke is 8/10 work on santa booms skill to 7/9. Reason is he is helpful in Here Be Monsters
Harpy Queen not really sure
Druid to 5/10 skill. When you get the 6th base it will need to be 5/10 to heal all 6 heroes.
Then for the 6th slot I would pick between Thunder God or Orksbane depending on how you play.
Thunder God is good for raising because of the ability to kill heroes if a hero killer place on the opposite side of a base of the town hall.
Orksbane is decent everywhere.
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