Steam are offering Divide by Sheep & Fearless Fantasy free until May 14.
Divide By Sheep is a mind-bending math puzzler about friendship and slicing sheep in half with lasers. The Grim Reaper flooded the world, and it's up to you to save critters stranded on islands. Insane math skills required.
Fearless Fantasy - rated mostly positive.
As Leon, the world’s most dangerous bounty hunter, you embark on a mission to slay the world’s weirdest creatures, and save a girl from an awful marriage.