Is there a list of what the skill levels are for each of the combat heroes and which should unlocked..

Every heroes 1st and 6th skill should be done first since it will give you maximum troops, but the 6th skill (awakening: requires duplicate of hero) also adds buffs like combat speed, resistance and others. The 2nd (req: 5 purp.), 5th (req: 1 org. + purples) and 8th (2x org) skills either do damage to the enemy/debuff or buff own legions. These 3 skills are all set with different ranges which will help you place the hero in front, middle or back. Finally skills 3, 4 and 7 give different enhancements to legions or specific troop types... exmp. Orochi and North Rage's 7 skill give 15% hp and 3-4 are resistance and might boosts. Now that I've confused you... go to the guides and click on hero skills and placement tab. This guide really breaks everything down and will help you going forward.