Want to play on MP maps against one or several AI opponents?

Isn't exactly a "HowTo" in the classical sense as you only have to add a single line. Maybe this is common knowledge but I've always liked the skirmishes more than the actual campaign. With this change, the "Multiplayer" menu ingame has a new option, "1 Player".

Windows: Add "-1player" to the game's .exe shortcut.
Like this: ".../somewhere/Dungeon Keeper/Keeper.exe" -1 player

Dos: Add "/1player" when executing the game's .exe.
Like this: C:\Program Files\Bullfrog\Keeper\keeper/1player

With GoG's preconfigured DosBOX version:
Modify the dosbox.DK.conf file in the install directory. Change the second to last line from "Keeper.exe" to "Keeper.exe/1player".

Have anyone tried this with the mac boxer edition? Any help on that would be greatly appreciated!

It's dosboxDK_single.conf rather than dosboxDK.conf and launch the game via multiplayer

maybe it changed since OPs post

I need help with the mac edition as well :/

Manages to get 1 player skirmish working on mac osx 10.11.2, DK installer version 2.1.0.24

Just need to edit two files. They are located as below -->

/Applications/Dungeon Keeper Gold.app/Contents/Resources/game/Dungeon Keeper Gold.app/Contents/Resources/Dungeon Keeper.boxer/C.harddisk/MULTI.BAT

/Applications/Dungeon Keeper Gold.app/Contents/Resources/game/Dungeon Keeper Gold.app/Contents/Resources/Dungeon Keeper.boxer/C.harddisk/MULTI_DEEPER.BAT

Just add "-1player" after the exe file on the last line. So they become:

@echo off
CALL NETWORK
imgmount d -t iso -fs iso game.gog
KEEPER.EXE -1player

and

@echo off
CALL NETWORK
imgmount d -t iso -fs iso game2.gog
DEEPER.EXE -1player

Then run as normal select the multiplayer option then host then you can selected 1player.

It might work adding -1player to the other launch option but not tested.

One player is one too many for my tastes. Is there a way to make that 0 players?

(In other words, is there a way to watch the AI play against itself with no human players?)

The simplest way is to play a 3 or 4 player map with the computer players and don't do anything yourself. You can use the cheat menu to get vision of the map, or you can use the editor to place a 'reveal map' special on the map.