Zup! is more than just a physics-based 2D puzzle series. It also happens to be a series bursting with Steam achievements and emoticons to collect.

These are two huge reasons that the series continues to draw hundreds of gamers upon each launch. It also helps that each game is quite cheap and casual to play. Zup! 4 follows in these footsteps with another title sure to make for relaxing gameplay sessions.

Zup! 4 is available on Steam with a launch week discount of $0.84. Unfortunately, there's not currently a complete series bundle available on the site just yet.