Garry’s Mod November 2025 Update: Water Upgrades, NPC Fixes, and More

The Garry’s Mod November update landed on November 12, 2025, and it’s a crowd-pleaser: better looking water, smarter NPCs, and a raft of quality of life tweaks without breaking your addons. Below we’ve pulled together the official highlights and what they mean for players, server admins, and modders who rely on GMod day to day.

Garry’s Mod’s latest update rolls out for November 2025

This patch focuses on two big goals: modernizing water rendering and cleaning up long standing NPC weapon behavior, plus UI polish and scripting improvements. The official dev post and changelogs confirm the release date and full feature list. 

Visual Overhaul - New water rendering and terrain blending

Water finally looks like it belongs in 2025. The update backports modern Source features: flow maps, lightmapped water fog, and 3D skybox reflection (support for $reflect3dskybox/$reflect2dskybox). Map water can now reflect the 3D skybox and behave more convincingly, while staying compatible with content from mountable games.

For level artists, the patch also adds the Lightmapped_4WayBlend shader (with tools support). This provides smoother 4 material terrain transitions compared to older 2 way blends, making cliffs, beaches, and ground detail look far more natural.

A quick compatibility note direct from the dev blog: some older maps used “borrowed” water materials with parameters that didn’t work before but do now, which may change how their water looks. The fix is to edit the material, not recompile the map.

For mappers wanting the deeper tech: Valve’s docs cover the Water shader (reflections/refractions/flow) and Lightmapped_4WayBlend (4 way displacement blending) fundamentals. 

Smarter NPCs and gameplay fixes

The headline gameplay change: NPCs finally handle a full range of weapons correctly. No more T-poses with non default guns; Combine Soldiers can use all built in weapons (even RPGs) and pursue players unarmed; Citizens can now keep firing while crouched; and several Half-Life 2 characters get proper “spawn with weapon” behavior. These changes make sandbox firefights and RP scenarios feel more consistent out of the box.

Beyond combat, there are dozens of stability and UX fixes, better invalid model detection, menu cleanups, and signed executables, aimed at smoother play and fewer crashes from troublesome addons.

Sandbox and interface improvements

Two small but welcome QoL tweaks: you can toggle the Spawn Menu and Context Menu (binds in Utilities → Sandbox), and the Creator Tool lets you pick the weapon used when spawning NPCs. Plus, Faceposer adds per category randomize/clear controls and there are subtle server browser and tab visual adjustments.

If you manage a public server, consider pairing these with ULX for permissions and moderation and a clear workshop flow for content distribution:

Technical updates and Lua API changes

Modders get a sizable Lua API refresh: new NPC helpers (e.g., NPC:IsCrouching, NPC:SetForceCrouch), new hooks (e.g., GM:OnNPCDropItem), mesh/renderer safeguards to prevent hangs after errors, and targeted optimizations (including GM:PlayerCanHearPlayersVoice work that reduces overhead on populated servers). Result: more control and fewer crashes from edge case scripts.

Under the hood, the engine gains flow- and fog capable water, 4 way blend shader, safer limits, improved .nav error handling, and server side conveniences (e.g., sv_nomap_timeout). These are quality of life wins for admins and scripters alike.

Addon compatibility and performance

The November update focuses on stability and compatibility. The official notes list lots of fixes and additions rather than removals; while a few deprecated bits were cleaned up, the patch does not introduce sweeping API breaks, and several changes specifically aim to reduce crashes and Lua edge cases. As always, check your critical addons, but most servers should upgrade cleanly.

If you’re staging a rollout:

• Switch branches (e.g., to pre release/x86-64) only if you need to test; otherwise stay on default until your must have addons are verified.
• Edit your command line to set map/workshop params cleanly.
• Set auto restarts to apply updates off peak.

For mappers and artists

You can now paint 4 way blends in Hammer, save time with improved model/compiler metadata, and mount CSS/Episodic VPKs directly in tools. Water materials that use $lightmapwaterfog (and flowmaps) now receive lightmaps on compile, improving realism.

Working on visual refreshes? Host custom maps safely and iterate.

A fresh coat of paint for a classic sandbox

Nineteen years on, GMod is still getting real engine level love. The November 12, 2025 update brought better water, richer terrain blending, smarter AI, and meaningful Lua improvements, with an emphasis on stability. If you just want a painless upgrade, let Steam patch and jump in. If you run a server, tick through the quick checks above and you should be golden.

If you’re looking for reliable hosting tuned for GMod’s latest build, check out Host Havoc’s Garry’s Mod servers: low latency locations, quick workshop sync, and proactive update support.