• 2 min read • Halo, HaloDecomp, PC Gaming, Multiplayer, Mods

HaloDecomp Shatters Engine Limits: 128-Player Multiplayer Running on Custom Map 'Extinction'

HaloDecomp developer Jonas Volman has showcased Halo: Combat Evolved running with 128 simultaneous players on the legendary custom map Extinction, demonstrating massive networking overhauls for the decompiled engine.

HaloDecomp Shatters Engine Limits: 128-Player Multiplayer Running on Custom Map 'Extinction'

In 2001, Bungie revolutionized console LAN parties by engineering 16-player multiplayer for Halo: Combat Evolved on the original Xbox. Twenty-five years later, the ongoing #HaloDecomp project has obliterated that historical ceiling: developer Jonas Volman (@bnununana) revealed that the decompiled Halo engine is now running with an astounding 128 simultaneous players on a single dedicated server.

The shared in-engine screenshot captures a surreal sight for Halo veterans: a troop-carrier Pelican dropship packed to the brim with rows of allied Spartans, with dozens of green friendly player chevrons crowded into the bay while the iconic "Running Riot! (14)" medal banner blares across the HUD.

HaloDecomp running 128 players on Extinction with Pelican troop transport
A Pelican dropship crammed with Spartans as 128 players deploy across the battlefield in HaloDecomp on Extinction. (Source: @bnununana on X)

The Return of 'Extinction'

The benchmark was conducted on Extinction, one of the most legendary community maps ever crafted for Halo Custom Edition (Halo CE). Originally developed by Dennis and the community in the mid-2000s, Extinction was famous for its gargantuan scale—featuring vast open mountain ranges, flyable Longswords, Seraph fighters, pilotable Pelicans, Scarab walkers, and multi-tier forward operating bases.

On original GBA and PC network stacks, hosting games of that scale was perpetually bottlenecked by netcode tick rates, packet size constraints, and hardcoded memory buffers that capped matches at 16 (or custom 32) players. By rewriting and recompiling the core network architecture in native modern C/C++, HaloDecomp enables true large-scale combined-arms warfare reminiscent of Battlefield or PlanetSide, right inside the original Blam! engine physics sandbox.

The Power of Decompilation

Unlike standard mod tools or memory injectors, static and source-level decompilations allow developers to completely decouple game logic from ancient 32-bit constraints:

  • Expanded Network Stack: Dynamic player allocation, modern reliable UDP sync, and raised entity/projectile limits.
  • Modern Platform Portability: Cross-compilation to modern 64-bit systems, native Linux/Vulkan renderers, and ultra-high tickrate dedicated servers.
  • Engine Fixes: Direct access to audio mixing pipelines (as hinted by the debug audio subtitle in the screenshot), high-refresh-rate animation interpolation, and native ultrawide HUD scaling.