Creator Killer: This was Roberta Williams' last game, and was one of the last adventure games released by Sierra.
Franchise Killer: The details are still hotly debated. The old fans hated the required action, which stood in such contrast to the series' previous position on violence. However, it supposedly sold much better than true adventure games of the same time period. Nonetheless, outside of fan remakes, the series would lay dormant for many years.
Genre-Killer: Frequently cited as one of the games in the late '90s that killed the adventure genre.
Some areas were cut for time constraints. The Swamp Witch was supposed to play a larger role, first appearing as a beautiful woman and trying to seduce Connor, instead of immediately attacking in her real, hideous form. A redcap goblin was scrapped that would have stalked Connor around and Connor himself was at one stage a statue who came to life while everyone else was petrified.
Another version of the game was to be made by Davidson & Associates, the creators of Math Blaster. Founder and devout Christian Jan Davidson, who at the time was holding a grudge against Roberta Williams for making the controversial Phantasmagoria Sierra's best selling game, saw how violent Mask of Eternity was looking to be and coerced CUC Software, the company that owned both Sierra and Davidson at the time, to allow them to make their own version that was more Christian-friendly, removing all violence and combat in the game, ironically making it more like a traditional King's Quest game. Roberta, feeling like she had lost control over her game, threatened to abandon the game's development entirely. It wasn't until Davidson got absorbed into Knowledge Adventure that Roberta returned to the game, but the damage was done and a bunch of stuff was cut due to lost time.