Downfall • lyonheart

Games Autumn 2025

by Matthew Lyon • November 10, 2025

Downfall is an endless runner-style game where you’re falling instead of running. Again working with my Phil Hagelburg in Fennel for the TIC 80 fantasy computer, as an entry for the 2025 Autumn Lisp Game Jam, with source code available.

Screenshot of the game, featuring a figure with a bunch of particles surrounding them, hovering far above some spiky-looking things — Keep on fallin’

I had just finished working on the audio for Cosmic Collision Course, an endless “climber” and recalled Downwell, which at one point occupied a lot of my phone time. I figured it would be fun to make something in the genre, and am pretty happy with how it turned out.

Screenshot of the game, featuring a red laser emanating downward from the player, and a lot of detritus particles from the swath of destruction in the player's wake — Navigating can be a challenge, but that’s what a laser is for.

Screenshot of the game, the game over screen with a big "splat" — Navigating can be a challenge, but that’s what a laser is for.

I worked mostly on controls & physics, graphics, and sound, while Phil handled terrain generation and difficulty tuning. While the graphics leans heavily on sprites and tiles, I think I really found my groove with particle effects in making the most of the TIC-80’s limited graphics system. We make use of palette swapping to have the game get darker as you progress further. The music is an entirely generative system, with the generated melodies becoming more discordant as you progress. I’m pretty happy with how the game turned out.