Hammerwatch v2.0.0.2 - GOG

http://www.gog.com/game/hammerwatch

4 different classes, with unique features and skills.
Multiplayer COOP, online, LAN and local.
Mod and editing support.

Hammerwatch is a fast-paced hack and slash adventure game, inspired by classic titles of the genre. In the old, mysterious, and not-so-abandoned Castle Hammerwatch a group of heroes must fight their way up through the floors to the very top of the castle, where an ancient dragon awaits them. Not only must they kill the beast, but also get back out in one piece!

Bring back your button-mashing hack and slash skills and fight thousands of monsters while avoiding traps, findng secrets and increasing your skills on the way up. Do it yourself or bring three friends for some great fast co-op action! Feel free to launch the editor and build your own adventure with your own graphics, or try out someone else's custom level!