Thanks for the feedback, and for playing :)
The saprophyte's "memory" is limited to being able to open tiers of locked doors, as well as assuming the form of the story-specific corpse in the Talisman AI Core - while its AI was the best I could do at the time, it's nothing too special.
The saprophyte AI is designed to patrol randomly, with a bias towards tiles it hasn't stepped on recently, and head towards new doors or yummy corpses (or the player of course) if it has line-of-sight. It uses invisible "heat" AI objects to determine if the player has recently been somewhere, used a Terminal, or opened a Door, so it does have some limited capacity to remain in an area you've been in recently. But the saprophyte's "intelligence" is, for the most part, smoke and mirrors :) But I'm happy that it can be mistaken for more clever than it really is :P
The sad thing is, there's a good chance you didn't see it again because it was thinking it was really sneaky and hiding behind a pillar waiting to ambush you... but you never came :/ like having a birthday party alone... (It hides behind foreground tiles based on simple conditional & collision checks)