Yes. Locomalito distributes 8Bit Killer as freeware from the official game page.

How large is the download?

The official Windows ZIP is about 16 MB, so it downloads and extracts quickly.

What platforms does 8Bit Killer support?

The official standalone release is for Windows.

No. 8Bit Killer is a keyboard-and-mouse single-player FPS, with no multiplayer or native controller support documented by the developer.

16 MB

Default bindings for every input method 8Bit Killer supports. These are the game's own defaults — anything you have remapped will differ.

Default keyboard and mouse bindings.

Movement — Mouse & keyboard
Action	Default input
Move	`W, A, S, D`
Jump	`Space`

Camera — Mouse & keyboard
Action	Default input
Look / aim	`Mouse`

Combat — Mouse & keyboard
Action	Default input
Fire	`Left Mouse`
Switch weapons	`1–5 / Mouse Wheel`

An NES run-and-gun fever dream rebuilt as a lean, vicious first-person shooter.

Interaction — Mouse & keyboard
Action	Default input
Use / open	`E`

Interface — Mouse & keyboard
Action	Default input
Pause	`Esc`

Verified against the game by PlayBound.