Wiki: Auto return - when troops in the world have finished solo battles, rally battles, and occupying land, they'll automatically go back to your castle. Upgrade skills: breaking down duplicate skill medals grants skill points which can be used to upgrade hero skills and increase their military power. When a hero reaches level 5, a second skill slot will be unlocked. A third skill slot will be unlocked when the first skill reaches maximum level and a level 2 talent is activated. Skill reset: from the hero skill details page, you can use reset skills to refund spent skill points. Focus on spending points to upgrade the hero's fixed skill to level 10 to unlock a second learnable skill slot. 100% of skill points used are refunded in the new player stage. Outside the new player stage, 80% of skill points are refunded.