FREE: Tumblestone [steam key]

The listing, Tumblestone [steam key] has ended.

http://store.steampowered.com/app/269710/Tumblestone/

Over the past 15 years, Tumblestone is the first non-standard dynamic puzzle game. Compete with friends or challenge yourself in the Scene Mode. Gradually solve more and more tricky and unusual puzzles, help Sosisko make friends and find out what happened to Kuvyrkorona.
Your friends play for free
You can create an unlimited number of free Steam keys and send them to friends for a joint online game, up to 5 games a day.
Main characteristics:
Incredible spirit of competition: Solving tricky puzzles with other players will turn your "a couple more rounds" into an endless night marathon.
Game on one device: Allows to play simultaneously 2-4 players on one computer.
Network game: Play on the network with your friends or find new ones thanks to a multi-level system of rotation.
Bots: Is there an empty seat? Fight with artificial intelligence. But is there anyone who can overcome the inexorable Nightmare?
Scene Mode: As you solve puzzles, you are waiting for more than 40 hours of fascinating story. More than 10 game modifications.
Arcade: Relax a bit and go into the zone with three arcade modes.
Leaderboards: Online leaderboards without unnecessary words will inform your friends who is the best in the game.
Quests: Hundreds of unique quests. And you weak?
Statistics: Hundreds of statistics parameters.
Personalization: The difficult choice of a dozen characters and design options.
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