Dragonite

Over 300 named color codes that you can add to GameMaker!
Fast(ish) sorting in GameMaker
Combine sprites into single atlases!
Try out different image blending modes quickly and easily!
A lightweight, generic inventory system for GameMaker Studio.
3D Cel Shaders for GameMaker Studio 2
Garbage-collected ds_lists in GameMaker
3D Lighting Shaders for GameMaker Studio 2
Convert between different 3D model formats for GameMaker (or anything else)!
I wanted to try my hand at an even worse sorting algorithm but chickened out.
Ever wanted a visualization of how your game's performing?
A Windows Forms-like graphical user interface library for GameMaker Studio 2.3
In case you ever need to drag files into a GameMaker window.
Do you like particles? I like particles.
See how your Scribble formatting looks in real time!
The (hopefully final) iteration on my old terrain editor
Easing curve math for use in Game Maker
encouraging project maintenance
Some types of variables can be accessed faster than others. Here's a test.
The solar system, in 3D. Sans moons. May add those later.

GameMaker - DDD

Useful Tools for Game Maker

Useful game assets