Sediment is a pixel-physics sandbox simulation game built around cellular interactions on PC. Every element behaves according to its physical properties rather than scripted visuals, creating emergent results from simple rules applied across neighboring cells.
Gameplay
The core loop centers on placing and observing materials that follow consistent physical laws. Fifty distinct materials exist in the base set, each defined by attributes such as density, phase, melting point, and absorption behavior. Sand settles into natural slopes because heavier particles displace lighter ones beneath them. Water flows and pools until it encounters barriers or evaporates under heat. Lava cools into solid stone on contact with cooler substances while releasing steam. Acid corrodes any material it touches until the reaction completes or the acid itself is neutralized.
Temperature spreads only through direct contact, so heat management requires enclosed chambers rather than open flames. Density determines layering without exceptions: gold always settles below lighter ores when washed into a basin because its mass pulls it downward through surrounding particles. Burning materials produce expanding gases that can ignite adjacent substances, while certain combinations like sulphur and cinder create gunpowder that detonates into hot gas rather than simply accelerating combustion. A spirit fuse carries flame along a trench to trigger distant reactions.
Simulation occurs at the individual cell level with no mass creation or loss outside explicit rules. The entire world operates as a grid where every exchange between neighbors respects conservation principles, producing predictable yet complex outcomes from basic neighbor checks.
Game Modes
Structured progression comes through nine lessons that introduce mechanics through direct experimentation instead of text explanations. Players manipulate materials in guided scenarios to discover interactions firsthand. Twenty tasks extend this approach with concrete objectives that encourage repeated testing of physics systems.
Freeform creation serves as the primary unstructured mode. Players draw materials onto the grid, adjust conditions like temperature or gravity indirectly through reactions, and observe long-term behavior. The built-in editor allows creation of custom materials defined by JSON parameters covering density, phase changes, melting targets, and absorption rules. These custom entries integrate directly into the palette without external tools.
Customization and Sharing
Material creation extends beyond the base fifty entries. A simple JSON format lets users define new behaviors that the simulation engine processes identically to official materials. Published packs appear in other players' palettes automatically when subscribed.
World sharing follows the same principle. Saved levels include references to required material packs, ensuring subscribers load the correct elements instead of default placeholders. This system supports community-driven content without compatibility issues.
Additional features include conversion of any local image into a material layout, full gamepad controls for precise placement, and support for twelve languages in the interface.
Is It Worth Playing?
Sediment suits players who enjoy open-ended experimentation with simulated systems over narrative or competitive goals. The cellular approach produces consistent, observable results that reward careful observation and iterative testing. Lessons and tasks provide entry points for those new to physics sandboxes while leaving room for advanced custom work.
Those interested in building and sharing their own rulesets will find the JSON editor and publishing tools immediately useful. The absence of external dependencies for shared content keeps the focus on the simulation itself. Players who prefer guided campaigns or multiplayer competition may find the experience narrower, but the core physics loop delivers depth through interaction variety rather than added systems.