Posted October 15, 2015
Engine dependent. Games may require them, or they may not. Some games can use the DLLs that are in the game's directory (and distributed with the game), others may not need any of them.
HiPhish: In case of a game written in an actual language you need compiled dependencies (DLL files and such), none of which are documented anywhere. That is what the installer is for, it installs these dependencies on your system.
Take Diablo 2 for example, or JA2. Move the installed files to any computer, and they work. Add them to a flash drive, play from said drive. No dependencies, all DLL files included with the games.
But again, if said games are distributed as zip files (or unpacked ones), they are not DRM-Free, because they don't have an installer.
P.S. What if there's a .bat or .cmd file that installs the dependencies, but you still get just a bunch of files and no installer? Does that change the DRM-Free status of the game or not?