Heroes vs Monsters is straight up built for fun. We've never experienced large scale, skill-based combat in such a simple and enjoyable format.
With four heroes and legions of enemies engaging in simultaneous battles, you'd expect things to get out of hand quickly. Not so. Within 30 seconds, the game's straightforward touch controls will have you commanding your troops with all the skill of a Starcraft veteran in his parents' basement.
Tapping a hero brings up their skills, while touching and dragging moves them or executes an attack. You can easily bounce back and forth between characters, sending one off to attack an enemy, choosing another to heal it while simultaneously retreating, and so on. The ease of control gives you the freedom to engage in simple combat or complex strategy...whichever your heart desires.