It is a clicker game in which you click monsters till their hp reaches 0 and earn coins to purchase weapons and armour. Some enemies may drop weapons rarely or commonly when they pass away.
You can also gain Experiences which once enough will level you up and increases your Total Health and Total Damage by 1%.
An Example you have 1000 hp because of armour so after level up it would be 1010 hp and will be 101 hp without that armour.