Dungeon Master II: The Legend of Skullkeep

Instead of using text-based commands to interact with the environment, players directly manipulated objects and the environment by clicking the mouse in the enlarged first-person view.

Abstract Dungeons and Dragons style experience points and levels were eschewed in favor of a system where the characters' skills were improved directly via using them.

It also introduced some novel control methods including the spell casting system, which involved learning sequences of runes which represented the form and function of a spell's effect.

For example, a fireball spell was created by mixing the fire symbol with the wing symbol.

This kind of attention to detail and focus on the user interface was typical of the game and helped create an often captivating sense of craft and ingenuity.

Other factors in immersiveness were the then-revolutionary use of sound effects to indicate when a creature was nearby, and (primitive) dynamic lighting.