Secret Adventure Mode
From Creatures Wikia
From: regen Subject: drowned god  Newsgroups: alt.games.creatures Date: 1998/02/25 Help! Does anyone know how to get back into the sun pyramid, in the Chesed time period? I went out before I finished my task and know there is a large sphere blocking the entrance. I don't want to have to start the game all over from the beginning. Thanks in advance.
David's (fictional) solution can be found here, but it must be read right to the end.
A prototype SAM is actually documented in Steve Grand's programming diary, in the week commencing 3/5/94 (3rd of May, 1994). It consisted of a possible sequence of events that might form a storyline.  Thankfully, the concept evolved to the level of complexity that we see today in the Creatures series.
Rumours that Creature Labs intended to expand the adventure mode into a separate game were deemed to be confirmed when details of Project Loci leaked - unfortunately, the company was liquidated before the game could be completed.
|Spoiler warning: Plot or ending details follow.|
C12DS contains the Creatures Secret Adventure Mode, and an unofficial, partial walkthrough has been created by Officer 1BDI for accessing it. Clucky later created a youtube video full walkthrough of the C12DS Secret Adventure Mode.