Dragon Hill is an insanely fun and thrilling action game where you, being a dragon rider, get to control a dragon. Not really sure what happened prior, but in this game, your goal is to apparently wreak as much havoc as possible in your quest to exact vengeance on the kingdom and its people. After all, the dragon will just gobble and destroy everything in your way and it is up to you to "direct" it towards things you want to smash or swallow whole.
Gameplay-wise, the game is really simple to grasp and play. You can get the dragon to dig deep by clicking on the screen and release your mouse button to make it leap from the ground like some sandworm from Dune. There are also coins that you'll want to collect as much of and, of course, you'll want to avoid any obstacles, whether it is a solid wall of spikes or a pool of bubbling lava.
Similar to Temple Run, the longer you travel across the land in Dragon Hill, the more coins you'll eventually accumulate. The coins you earned can then be invested into various upgrades like getting your dragon some armor or improving your attacking abilities and increasing your revive chances.