Limited, but with good potential!
The game starts off very easily and overpowered, but the difficulty rating climbs significantly around halfway through. I had maxed out all my upgrades by level 6 (starting with strength, so any arrow was essentially a one shot kill for many enemies), but around the time catapults and dragons were introduced, my archers died before I could heal them. In fact there were so many flames and arrows flying towards them I couldn't see how much health they were on because their health bars were covered by the enemy attacks. Unfortunately, despite my impregnable walls and their ridiculously high health, I could not see where they were aiming so I had difficulty returning fire and they all died. I think this is a simple thing which more or less ended the game for me. Still enjoyable, but if you improve slightly on visibility of your archers, and give a tutorial that you can click through rather than sit through it would be appreciated. All in all, a fun few minutes.