In Cryptozookeeper, you attempt to solve puzzles and quests in order to find different kinds of DNA with which to make over 60 possible cryptids. There are over 200 characters total to encounter, and a Creative Commons-licensed soundtrack of 70 songs. A character-driven work with a full text parser and graphics, Cryptozookeeper features over 12 hours of gameplay in the Infocom tradition.
This game requires an interpreter, which you can download for free (Intel or PPC) here: http://www.ifwiki.org/index.php/Hugo