Play Portal Knights for Free

Portal Knights is free-to-play on Steam for the next day or so, accompanied by a sale on the Windows action/RPG if you enjoy your sample when it ends tomorrow (thanks SteamDB via Ant). Here's word on the game:
Prove yourself a Portal Knight by levelling up your character, crafting epic weapons, and vanquishing foes in real-time in this cooperative, 3D sandbox action RPG.

Explore dozens of randomly-generated islands! Build almost anything! In a world torn apart by the Fracture and terrorized by the Hollow King, you and your friends are its only hope!

Craft your adventure. Forge your hero. Become the ultimate Portal Knight!