It runs in real mode but can make use of the high memory area.
However, to obtain this, it must be run in combined mode.
Many 386 computers ran Windows 3.0 in standard mode due to a lack of memory and also for performance reasons.
Running in "checked mode" is recommended for development and testing.
These additional registers are only visible when running in 64-bit mode.
Some software is therefore designed to run in conversational mode.
This prevents programs running in protected mode from interfering with each other's memory.
This offered better quality than running in pure 16-bit mode.
A program can be set to run in "global" mode as well.
It is one of the few commercial games to run in native mode on the Commodore 128.