The Kalimba - The Dark Void - Coop Add-on for Kalimba has 5 achievements.
Achieve an all golden The Dark Void Coop Totempole
Complete the Dark Void co-op
Squash the seeker in "Jeffmoldblum"
Squash 12 seekers at once
Play through "DJ Steelface" twice, in one go, without dying