Setting up Heroes of Might and Magic III with Horn of the Abyss (HotA) expansion on modern high-resolution Windows PC

Intro

Hello!
I'm a casual gamer and I decided to write a detailed guide on how to set up Heroes 3 for modern PCs, including the HD mod and the HotA expansion.

Goal

The goal is simple: to be able to Play Heroes 3 + HotA in HD, while the game time is tracked by GOG

Steps

1. Buy the game on GOG: Heroes of Might and Magic® 3: Complete.
2. Download and install GOG Galaxy
3. Install Heroes of Might and Magic III: Complete on GOG Galaxy
4. Use the shortcut on desktop to launch the game, make sure the game starts (wait intros, etc.), then exit the game by clicking the Quit button in main menu.
5. Download the HD mod here: HoMM3 HD+ - Download, then install it.
6. Download the HotA expansion here, then install it.
7. Open GOG Galaxy 🡲 GAMES section on the left 🡲 click Installed 🡲 find Heroes III 🡲 right click 🡲 Manage installation 🡲 Configure... 🡲 Click FEATURES tab on the right 🡲 ✅(tick) Custom executables / arguments 🡲 Scroll down to the bottom 🡲 click Add another executable / arguments 🡲 select HD_Lanucher.exe in the game folder, then click Open 🡲 this creates a new entry on the bottom, in the list you are currently at, find it (you will see HD_Launcher.exe), then ✅(select) Default executable 🡲 click OK.

Now, you can use the desktop shortcut (created by GOG Galaxy) to start the HD Launcher, which can be then used to start any version of the game (either Heroes 3 Complete with HD mod, or HotA with HD mod).

Note that the GOG Galaxy will track the time spent while the HD Launcher is open, this means two things:

• ⏹️(don't tick) Close after launching the game in the Launcher Settings tab (if you do, your game time won't be correctly measured)
• if you want precise game time tracking, then don't leave the game launcher "hanging" in the background because this counts as you playing the game which you don't want

Settings for HD mod

Since I have seen multiple requests for help regarding how to set up HD mod settings for the best experience (and I have also spent too much time on that), I share the settings I have found to be the best for me:

Graphics

• ✅(tick) Full screen mode first
• Mode: (stretchable) 32-bit GDI
• Source size: see below ↓
• Stretch filter: Bilinear 2xSharper
• Render threads: (leave as is)

Source size

The most simple advice I can give:

• if your monitor is 1920x1080 (Full HD) or 3840x2160 (4k), use 1280x720
• if your monitor is 1920x1200, use 1280x800.

More detailed explanation:

• Always match the Aspect ratio of your monitor – if you don't know it, see What Is My Resolution & Aspect Ratio, find "The aspect ratio is ...".
• The bigger resolution you choose, the smaller game elements will be, so find your sweet spot.

Tip: Use the tables at the bottom of the page to find some resolutions to try for your aspect ratio.

Comments / details on steps

1. Tip: The game is regularly on discount. For example, on 2025-04-18 it was available for purchase for €2.29 (-75%).
2. --
3. Open GOG Galaxy 🡲 GAMES section on the left 🡲 click Owned games 🡲 find the game (use search if needed) 🡲 right click 🡲 Install 🡲 ✅(tick) Create desktop shortcut and ⏹️(don't tick) Keep this game up to date automatically 🡲 click Install 🡲 wait until game is installed (you will see a toast notification in the bottom right, saying "Game installed") 🡲 Done!
4. --
5. When asked, select the folder you installed Heroes III to. ⏹️(don't tick) Create a desktop shortcut because it isn't needed. At the end, ⏹️(don't tick) Launch HoMM3 HD+ because it is not needed.
6. When asked, select the folder you installed Heroes III to. ✅(tick) Enable Auto Updates and ⏹️(don't tick) Create a shortcut on desktop.
7. --

Further advice

• The Heroes® of Might & Magic® III - HD Edition version on Steam has nothing to do with the HD mod. People usually strongly advise NOT buying/playing this version.