The Powder Toy

The Powder Toy is a falling-sand game originally created by Stanislaw K. Skowronek (also known as Skylark). It is now developed and maintained by LBPHacker, Simon, jacob1 and other contributors on GitHub. The Powder Toy is free and open-source software licensed under the GNU General Public License version 3.0. A total of 193 (more may have been added since this data was gathered) different in-game materials (or "elements"), each with custom behavior and interactions, are available in the game.

Gameplay Overview
The Powder Toy (abbreviated TPT), like most falling sand games, is a sandbox video game that allows users to create things in-game to share using TPTs online level sharing system, which includes a Front Page (FP), Recent tab, Favorite tab and a My Own tab.

A public server for sharing in-game creations is provided as part of the game itself, allowing users to share anything that abides by the rules. Examples of player shared creations include functioning circulatory systems, nuclear power plants, nuclear bombs, and computers. Content is rated using upvotes and downvotes, and can be reported to the moderators if it breaks the on-site rules or plagiarizes other works.

Modding Capabilities
TPT allows users to change TPT itself (Mod) with Lua scripting, and C++ coding, as TPT was made using C++. The source code is available on GitHub and can be compiled using Meson.

Mod Manager
A mod manager (hosted on starcatcher.us) can be downloaded using the console with the following command:. It works on all versions of TPT.

Popular Mods
Many TPT users have created C++ mods and Lua scripts. The most popular of which include: TPTMPV2 by LBPHacker, SpikeViper's Biology Mod by SpikeViper, Jacob1's Mod by jacob1, and TPT-Ultimata by Lord_Bowserinator. The former is a Lua script and the latter three are all C++ mods.

April Fools
The developers usually host an April Fools joke every year. Notably, the 3D mode feature was added as an April Fools joke, alongside the addition of a new fake purchasable in game currency called Powdercoins. Normally all April Fools update features are removed very quickly after April Fools, and it is rare that any of them stay in TPT in the long term.

Reception
edgalaxy.com called The Powder Toy a "great science game" for its potential use as a learning aid through its accurate portrayal of physics, chemical reactions and more.