A downloadable game for Windows, Mac OS X, and Linux

Inv8r (pronounced "invader") is an arcade-style robot shooting game with 60 procedurally generated levels. You control a cyborg secret agent infiltrating a series of increasingly well defended alien robotroid bases. You must fight to survive, navigate through darkness, and replenish your oxygen supply while facing killer robots, evil agents, and insidious alien overlords in a fast-paced paranoid bullet-hell game inspired by Berzerk, Dark Cavern, and Space Panic.

NEW! May 28, 2016: version 2.5! With the following changes:

  • Security stations fight back by firing sprays of bullets.
  • Touching the walls drains your oxygen instead of causing instadeath.
  • Fixed bug where barriers could still kill invincible player at level start.
Features both local co-op and client/server network co-op. (The network play code is still in beta and you may experience glitches. Please report issues to me at dto@xelf.me)


  • Expanded optional megaquest with 100 levels
  • More crazy robots with better AI


  • Hold the fire button (or SHIFT key) to lock the firing direction while moving independently. Use this when firing at a group of enemies, or trying to sweep a line of bullets across an enemy's path. Especially effective with Rapid Fire powerup.
  • Stay out of the screen's corners --- you'll get cornered.
  • Save oxygen tanks that appear early, so as to maximize the benefit of refill.
  • Don't touch the walls.
  • Don't rush into enemy groups. Peck around the edges instead.

Visit the DevLog and give feedback here: https://itch.io/t/23021/inv8r-you-versus-the-robot...

I'm making this in Common Lisp for the current #LispGameJam! https://itch.io/jam/spring-2016-lisp-game-jam

This is a work in progress. Some features are not yet implemented.

Install instructions


Unzip the ZIP file and open the resulting folder. Double-click inv8r.exe to begin the game.

  • This game is not compatible with DEP (Data Execution Prevention) on Windows, and will crash unless DEP is disabled for inv8r.exe. (It is NOT necessary to disable it system-wide; you can turn it off per-application.) See here Microsoft's notes on Configuring DEP: http://windows.microsoft.com/en-us/windows7/Change...
  • You must plug in any USB gamepad before starting the game, or else it will not be recognized. Xbox 360 game controllers should work if connected via USB.
  • The Analog Mode button must be activated for the analog stick to work. Otherwise, you must use the D-pad.


Extract the files from the archive; the binary is called inv8r.bin.

  • Linux users will need to have installed the SDL 1.2 libraries for IMAGE, MIXER, GFX, TTF. If you get a console error about SDL-GFX, try choosing the CONTINUE option and the game should run. (I am working on a fix for this.)

Mac OSX:

Extract the app from the DMG archive, and open the app. You may see a message about inv8r being from an "Unidentified Developer". Select "Open" again, and your preference will be saved. (You may wish to read Apple's notes on configuring Gatekeeper: https://support.apple.com/en-us/HT202491 )To read the copyright information files referred to on the title screen, right-click to open the app's context menu, and choose "Show Package Contents." (Or, use the Finder's "Go To Folder" function by pressing Command-Shift-G, and open the app.) Inside the subfolder "Contents" you will find the text file COPYING and the Licenses subfolder.


inv8r-windows-2.5.zip (51 MB)
inv8r-linux-2.5.tar.gz (52 MB)
inv8r-2.5.dmg (55 MB)

Leave a comment

Log in with your itch.io account to leave a comment.