GRAIN ROT controls: keyboard, mouse and controller
Quick answer
GRAIN ROT uses the standard first-person layout: WASD to move and strafe, the mouse to look and aim, Space to jump or vault, the left mouse button for your primary action and the right mouse button to inspect or use a secondary action. Steam lists full controller support, but the developer has not published a keybinding sheet — so the layout below is the one player guides record, and you should confirm your own bindings in Settings before your first descent.
Keyboard and mouse at a glance
| Input | Action | Why it matters |
|---|---|---|
| WASD | Move and strafe | Movement is your main survival tool. The Corrupted are faster than a straight fight with a starter tool, so most of the game is really about the space you leave yourself. |
| Mouse | Look and aim | Aim drives the charged swing as well as your camera, so the mouse is doing two jobs at once. |
| Space | Jump or vault | Vaulting is how you leave a bad room. Most crews die because they tried to win the fight instead. |
| Left mouse | Primary action — swing your tool | Holding the swing charges it. Player guides report that charged swings burn a large amount of the Spark energy bar. |
| Right mouse | Inspect / secondary action | Community guides describe this as the observe key: point it at a Corrupted, a piece of furniture or a fixture to read what it is. |
| Settings menu | Rebinding, volume, captions | Confirm your bindings here before a run. In-game remapping menus are limited, and Steam Input is the practical route on PC. |
The right mouse button is a mechanic, not just a binding
The observe key is the one input worth practising, because it is a game mechanic in disguise. Community guides describe pointing it at a Corrupted, an item or a fixture to read what the thing actually is — and in a game that deliberately shows you almost no numbers, that is a large share of your information.
It is also how you tell scenery from salvage before you commit a swing to it, and how you work out whether a body ahead of you is worth a detour or worth avoiding entirely. The store page is explicit that the Corrupted react to sound, movement and each other in unpredictable ways, so inspecting first and swinging second is the habit that keeps runs alive.
Two control states: vessel and Spark
GRAIN ROT hands you two different bodies worth of control, and the second one is where new crews panic. Knowing which state you are in changes what you should be doing.
| State | What you can do | What ends the run |
|---|---|---|
| Vessel — your wooden body | Move, swing your tool, haul loot, take hits, barricade doors with furniture. | The vessel splinters, collapses or catches fire. You do not die with it — the Spark escapes and the run continues. |
| Spark — no vessel | Community guides report a charged swipe that does little damage plus the observe key, and no way to carry loot. | A decaying energy bar. It drains over time, charged actions burn it faster, and when it empties you are out of the run for good. |
Controller, Steam Deck and Steam Input
Full controller support is listed on Steam, and Xbox pads are the common case. Keyboard and mouse remain the primary PC input, so nothing is gated behind a controller.
Mixed crews are normal online. One player on a pad and another on keyboard is a perfectly standard GRAIN ROT lobby, and no in-game advantage is attached to either device.
Rebinding: because no keybinding sheet has been published and in-game remapping menus are limited, Steam Input is the practical way to remap a PC controller.
Steam Deck: not officially rated at launch. The system requirements are modest — a GTX 970 and 8 GB of RAM at minimum, 10 GB of storage — so the bottleneck is more likely to be the rating than the performance.
Accessibility and audio options
Steam records accessibility features for the game, including audio options and full controller support, and its feature list covers captions and custom volume controls. That matters more than usual here. The Corrupted hunt by sound, and a Grinder running at full volume next to a stealth section is a genuine problem, so turning effects down changes how the game plays as well as how it sounds. Check the exact menus in Settings when you start.
Before your first descent
Open Settings and confirm four things: that the swing button is where your hand expects it, that the observe binding is reachable mid-chase, that the effects volume is not so loud you miss approach audio, and that your vault key works for the gap you actually intend to cross.
Then agree on house rules with your crew. The one that shows up again and again in community discussions is a noise rule — no gunfire until extraction is called, or until an Elite appears — because a single loud mistake pulls the whole floor towards you.
Confirmed facts vs community reports
The Steam store page confirms full controller support, keyboard and mouse as the primary PC input, and that the Corrupted react to sound and movement. The WASD, mouse, Space and mouse-button layout above is the standard first-person arrangement recorded by player guides rather than an official published sheet, and both the observe function of the right mouse button and the Spark energy bar come from community guides. Verify all of it in Settings — the developer continued to polish input after the demo.