A downloadable game for Windows and Linux

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This is a Super Crate Box mod that introduces local and online multiplayer modes with support for up to 4 players.

The source code was obtained via Humble Bundle.

Multiplayer-related code was heavily reused from my existing projects.

Additional notes:

  • A somewhat-stable internet connection and latencies under 100ms are highly recommended for playing online.
  • Online multiplayer requires port forwarding. This requirement may be lifted in the future updates.
  • At the time there are no Mac/Linux versions but the game should run well enough via Wine/Crossover.
  • This is a free user-created mod that is not affiliated with Vlambeer.
    Donations (if any) go towards producing more multiplayer games and experiments.
  • Given that this mod is rather experimental, you may encounter bugs or problems. Do tell if something breaks.

Have fun!


Download NowName your own price

Click download now to get access to the following files:

SuperCrateBoxTogether-1294-windows.zip 5 MB
SuperCrateBoxTogether-1294-linux.tar.gz 5 MB


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Cooles Spiel :D

como se juega online

Thanks so much for making this! Just what me and my brother needed! :)

I don't understand witch ip I need

you should make it so that player 1 could use WASD and F to shoot and player 2 uses ARROW KEYS and CTRL to shoot.

(if your wondering why, its because i dont have controllers)

You can open "%LOCALAPPDATA%\SuperCrateBoxTogether" in Explorer, open "controls.ini" with notepad, and edit controls to whatever you want.

Deleted post



action number 1

of Async Event: Networking

for object obj_dp:

Wrong gml type for buffer type

(Edited 2 times)

Hmm... perhaps assuming that the game would work fine after 3 months worth of software updates wasn't a wise plan. What did you do prior to the error appearing?

Edit: Okay, seems like the error occurs only in non-debug versions of the game on players joining. This will be fun.

The error happened when we tried to connect to each other. The ports were fine and such but in many occasions the above error popped up, or the game ends up crashing.

It turns out that `[@]` array read operator (`myvar = array[@index]`) is completely broken in GameMaker, just returning 0 both if reading out of bounds and if applied to something that isn't an array at all. Previously I was lucky (or careful enough) to not have made any missteps with this (thus not even knowing of this behaviour), but somewhere in the recent changes a bug was introduced, so GM' runner gets a 0 instead of showing an error, then it passes 0 as the index to one or other data structure management functions, and then everything spectacularly explodes before you could even blink.

I've re-enabled an older (working) version of the game for now while I'm looking over the game code to change everything to use `[]` operator for reading so that I can locate the actual source of problem.

Do you have the source available? I was on and off working on a two player Super Crate Box since the source became available and just found this. I want to see how you've done it. Thanks!

This is based on Humble Bundle version of the game source code.
The source for my edited version currently is not available (quite rushed, and, as it turns out, largely working by series of coincidences), and it doesn't seem to be legal to redistribute the edited sources for anything from the bundle but Spelunky (which was already open-source).

But basically, for local multiplayer, you just need to have each projectile store the ID of the player that fired it, and change things like "Player.x" to get that from the correct player (nearest for AI, owner for bullets, all for conditions). Then it's just lots of small edits like making laser guns not fly out of all players when firing.

I ended up changing a substantial amount of code in the game, but that was largely related to online multiplayer, and unneeded if that is not your goal.






God bless you and the internet.