Nuclear Throne Ultra mod was a solo project. It was a side project that I was working on alone in my free time. This project is a mod for a game called Nuclear Throne developed by Vlambeer. The mod adds all kinds of new features and balances the game as well.

Engine Game Maker Studio
Role(s) Programming (GML), Design, Pixel-art
Time January 2016 – August 2016 ~ 8 months
Hardware PC

My work

During this project I was doing a lot of scripting, tweaking variables and even community management. I did a lot of pixelart  and made some sound effects. I also designed a lot of new game mechanics and weapons.

  • Weapon design
  • Enemy design
  • Class design
  • Balance
  • Game feel
  • Random level generation
  • Community management
  • Pixel-Art

I was updating the mod every week. It ended up growing big and at some point a total of 2.000 people downloaded the new updates every week. It also got a lot of attention on youtube and spawned a ton of let’s play videos.

Fan made trailer below.


An appeal of mods in games is that it can step outside of the original game’s theme. Very often this would also include overpowered weapons and ridiculous things. I wanted this mod to be somewhat balanced and not over the top, Nuclear Throne is already pretty over the top in terms of its weapons. A lot of the community suggested weapons to me. It was important that I filtered the bad and good ideas and turned these into weapons that would be fun to use and balanced.

Weapon Modifications

I added a ton of things including weapon modifications which was quite a task since the game was not designed and developed with this idea in mind. I had to work around and be creative in terms of scripting.


Most people who played this mod had a fair bit of playtime and knowledge of the original game. This allowed me to add more complexity to Nuclear Throne. However very often the community suggested ridiculously complex ideas that didn’t add enough depth. For example a gun that fired a missile which the player could then control using different buttons on the keyboard.

Weapon Families

A lot of weapon families were added all of them with a distinct name and art style. Some of the added weapons were part of an already existing weapon family. The names were so recognizable and similar that people would often just not pick them up when they were underpowered at some point in development.


Nuclear Throne uses a level generation system. The version that I modded had a ton of issues in this system. Enemies would often spawn too close to players there was little cover and the variety in level generation was also little. I tweaked all of these things and added new levels with interesting elements such as ground that can burn or freeze the player. These levels require the player to pay more attention to their positioning. In the end the levels feel different and fairer because of these changes.


I added a lot of new characters that would vastly alter Nuclear Throne’s play-style. I knew the design philosophy of Nuclear Throne. No cool-downs and everything is fast pasted action. However I wanted to explore what a more tactical/slower or economy based play styled would look like. One of the characters I added can slowly fill the level with its own cover. Another one has a huge benefit for throwing weapons away instead of using them. Many characters make interesting use of the recourse systems in place. One character could use the experience you gain in the game as money to buy new weapons or upgrades. Another character can trade health to duplicate itself for more firepower.

There is a ton of let’s plays on the mod. It is great to see people enjoy it and use the gameplay to improve it.