Rex Engine: Advanced 2D Game Engine for Unity

Rex Engine is a 2D game engine for Unity focused on making your game feel as good as humanly possible. It gives you all the tools you need to get your game up and running quickly and easily, and can even help you create games with no code!

Click here to play a demo of Rex Engine!

The core of Rex Engine is a custom 2D physics engine which focuses on flawless precision. It takes its inspiration from the classic games of the 8 and 16-bit eras, when physics were 100% stable, digital, and videogamey. Rex Engine doesn’t simply work: it feels amazing while doing it.

Beyond the physics, Rex Engine gives you access to a huge variety of character mechanics and abilities. You can make both the player and the enemies move, jump, climb, use attacks, and much more — all with the press of a button! After all, the classic games are classics for a reason, and they’ve been around for ages; why should you have to reinvent the wheel every time you make a game that uses them?

Rex Engine: 2D Games made Easy

Rex Engine doesn’t just do the basics, either. It’s not afraid to roll up its metaphorical sleeves and help you with the nitty-gritty advanced stuff: you can alter or even reverse gravity, make the player or enemies take multiple types of damage including damage-over-time (heya poison!), and feel like a superhero by spiking bullets back at your foes.

What Makes Rex Engine Awesome?

We Can Barely Fit Everything in This Box!

Pixel-Perfect Physics!

Tight, responsive, pixel-perfect 2D physics, including flawless sloped terrain! Beyond simply working, Rex Engine’s physics have been exhaustively fine-tuned to provide that classic feel.

Classic Game Mechanics!

Run, jump, swim, and even fly!. Create characters that play like a myriad of classic game heroes! Rex Engine lets you make games in the style of Mario, Mega Man, Castlevania, and everything in-between! You can even give enemies all the same abilities you can give player characters!




Attacks Galore!

Shoot projectiles, swing melee weapons, bounce on enemies, and even reflect bullets!



Powerful Inspector Features!

Quickly and easily adjust core character stats like velocity, acceleration, and jump height. Go in-depth and tweak mechanics to your exact specifications! Want a dash-jump that retains its momentum when you jump and lets you initiate it in the air? Make it happen right from the Inspector!


Hot-Swap Entire Character Movesets on The Fly!

Give actors unique properties and animation sets for land, sea, and air movement, and toggle between them instantly with the push of a button! Want a character to play completely differently in the water? In the air? In any other circumstance you’ve invented? Consider it done!


Control Gravity!

Want moon physics, unique water physics, or even reverse gravity? Rex Engine does crazy stuff like that! You can even make characters that flip their gravity when they jump, VVVVVV-style!


Crunchy Effects!

Spice up your game feel with hit sparks, screen shake, sprite flash, sprite jitter, and more! Rex Engine doesn’t just function — it FEELS good!

Endlessly Extendable!

Rex Engine is carefully documented and has clean, commented code. You can use it as a foundation to build on, or even mix-and-match only the pieces you want to use. Just want to use the physics? Want to add your own mechanics? Rex Engine has you covered.

Assemble Full Games!

Rex Engine includes tools to put levels together, tie them in with additional scenes like the title and ending scenes, and add vital features like checkpoints and level-complete markers. It’s the whole package!