Maybe in the first 5 hours of game, it might be a little bit difficult. But once you get the hang of it, it's just way too easy.
And combat is too easy because AI is too stupid!!
As we all know, the best and the basic strategy in a turn-based game is to minimize your enemies' active units, either by destroying or controlling. So, the most important thing in the battlefield is to focus your firepower and avoid being controlled. And in this game, ranged enemies like archers and mages have the most effective controlling skills. And they usually would try to use them the first chance they get. So, you should control or destroy them before they had a chance.
So my team consists of 2 melee, 1 ranger and 1 mage. Ranger has glass cannon and bully, so she can kill distant controlled units with ease. Mage has fire, air and water magic.
At the first round of battle, I would try to control enemy ranged units like archers or mages. Most of the time, you will face 2 - 4 ranged enemies. So my 2 melee can use Crushing Fists to stun 2 units, and Mage can teleport one right between 2 melees. In the next 2 rounds, I would try to destroy all enemy ranged units. And if sh@t happens, I send one of the melee to get close to distant dangerous unit with Battle Ram.
About the 3rd round, enemy melee would be right next to my units. But I already finished all the units that had control skills, and I can finish the rest with ease.
Sometimes you would face too many ranged enemies or too many melee that you can't fight with this strategy. That's when you can use terrains to aid you. Just put all your units in a corner behind a tree or a stone, so that the enemy can't attack you in the first round and they have to get in front of you. Then send one of your unit to start the battle and get back into cover. By the time enemies get into attack distance, you would have saved enough APs and you would have them crowded in the same spot. Just finish them with aoe damage.
I have been using this strategy from lvl 4 to lvl 12. AI always react the same way!! The most challenging battle is against the Source King. But there is a trick you can use to finish the battle with ease.
I know that there is no chance devs can improve AI. I just hope you can do it better in the sequel. For example, if AIs are guarding a secret entrance, they shouldn't be come chasing me, and the should hold their ground and try to find cover. And if AIs are attacking, they should try to focus their firepower and pick off the most dangerous unit I have.
And seriously, you should find a grown-up story writer. NPC just nags too much, no human beings talk like that.
And some quick suggestions.
1. About click and enemy unit. You can use your skill and click target's icon in the top of the screen. Why not add a key, such as 'SHIFT', so you can just click the icon of the enemy.
2.No key for switching quick skill list? Seriously? Why put 3 lists in the first place?
3.Add a hint to whether you have read a book when you check the book.
4.Add mining sound effects. Serious immersion breaker.