Subroutine 616 is a browser-based retro-terminal horror game built for the Rive Halloween Challenge.

I wanted to explore how far I could combine Rive's runtime state machines with custom WebGPU shaders to build a tactile, atmospheric interface.

What it includes: • 3 playable containment stages: a hardware terminal with keypad entry, a perspective crypt chamber, and a reactor core with analog gauges and damper switches. • Dual narrative pathways: branching playthroughs ("Take Me to Hell" vs. "I'm Scared") that alter the atmosphere, visual corruption, and story resolution. • Speedrun Hall of Fame: session timer tracking containment speed, with a live community leaderboard and an in-engine procedural vector card generator for completion records. • Original Soundtrack & Audio: bespoke ambient horror scores featuring creepy boy soprano vocals, clockwork bells, and night crickets, paired with tactile mechanical switch SFX. • Rive State Machines & Vector Artboards: used for interactive dials, airlocks, and tactile UI elements, bound directly to game state variables. • WebGPU Shaders: custom WGSL passes for CRT curvature/scanlines, raymarched mist, and singularity distortion (with WebGL fallback).

Built with vanilla HTML/CSS and JavaScript to keep it lightweight, performant (60 FPS), and responsive across viewports.