Thief: The Dark Project (Thief Gold)

Install method
Thief Gold is on Steam (App ID 211600, ~$7) — install it like any other Steam title
and run it through Proton. ProtonDB rates it Gold (trending Platinum, ~69 reports);
it is not Steam Deck "Verified" but plays well after the steps below. It is also sold
on GOG; if you use the GOG copy, install via Heroic and pick GE-Proton (latest stable).
Either way the game ships as thief.exe in the install folder (Steam path:
steamapps/common/Thief_Gold/). Force a recent GE-Proton (or Proton 9.x / Experimental)
in the game's Compatibility properties.

TFix — NewDark community patch (essential)
TFix (by Tannar/community, built on the NewDark engine update) is the essential patch
for modern Thief Gold. It fixes crashes, restores cutscenes, adds widescreen support,
and greatly improves stability under Proton. It patches the game in place — it does NOT
add a separate launcher, so you still launch thief.exe afterward.

IMPORTANT INSTALL METHOD ON DECK — USE THE "LITE" ZIP, NOT THE INSTALLER EXE:
1. Get TFix from the official TTLG forum thread or ModDB (see links below).
2. Prefer "TFix Lite" (a plain ZIP). The full self-extracting installer EXE runs a
setup wizard that is awkward under Proton; the Lite ZIP avoids that entirely.
3. In Steam, right-click Thief Gold → Manage → Browse local files, then extract the
ZIP contents into that folder, overwriting/replacing duplicates when prompted.
4. Edit cam_ext.cfg (or run TFix's config) to set resolution:
game_screen_size 1280 800
(1280x800 is native Steam Deck resolution)
5. If you must run the full installer EXE instead, do it with protontricks pointed at
App ID 211600 so it lands in the correct prefix.

Steam Overlay
The Steam overlay can cause flickering/rendering glitches in DarkEngine games. If you
see graphical corruption, disable it in Properties → General → "Enable the Steam Overlay
while in-game". (On a GOG/Heroic copy added as a non-Steam game, disable it on that
shortcut's per-game properties.)

Controller
Thief Gold has no native controller support. Recommended approach:
- Use Steam Input with a community layout for "Thief Gold" or "Thief 1".
- Right trackpad = mouse look, right trackpad click = use/attack.
- Left trackpad = lean left/right mapped to Q/E.
- This is a first-person game — trackpad mouse look is more natural than joystick.

Audio
With TFix/NewDark installed, set the audio backend to OpenAL in the game's video/audio
options (or via TFix's config tool) — it is the most reliable mode under Proton and
avoids legacy EAX/A3D errors. If audio still fails on launch, you can disable EAX in
cam.cfg as a fallback.

Performance
The DarkEngine is single-threaded and CPU-bound on one core. Runs at 60 fps easily.
No TDP limits needed. Excellent battery life.

Save System
Thief uses a per-mission save system. Use F5/F9 for quick save and load. Save before
attempting difficult sections — the game is unforgiving.