Tibers Box 2 is described as 'Tibers Box is a physical and a sandbox construction, based on the manipulation of various objects. Manipulation of objects can hold a great variety: from stretch an object and applying it to different types of textures to create a flying machine' and is a Sandbox Game in the games category. There are 2 games similar to Tibers Box 2 for Mac, Windows, Linux, Steam and SteamOS. The best Tibers Box 2 alternative is Garry's Mod. It's not free, so if you're looking for a free alternative, you could try Golems Universal Constructor.
Garry's Mod is a Sandbox Game based around the idea of building. Unlike most other games there aren't any objectives - you can't lose and you definitely can't win. Doesn't work on MacOS 11.15 or higher.
Garry's Mod is the most popular Windows & Mac alternative to Tibers Box 2.
Garry's Mod is the most popular commercial alternative to Tibers Box 2.
Golems Universal Constructor or Golems is a 3D recreational physics simulator.
Build robots, spaceships, clocks, catapults or cannons.
Add sensors, timers, switches, motors. Give it a brain. Make a mouse trap - or make a mouse.
Take the wheel and pilot your machine yourself.
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Golems Universal Constructor is the most popular Linux alternative to Tibers Box 2.
Golems Universal Constructor is the most popular Open Source & free alternative to Tibers Box 2.
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As it is described on it's official website, it is free. it is also open source, so you can do any modification you want.