Infocom

Infocom released these text adventure games for the TI-99:

• Zork I: The Great Underground Empire
• Zork II: The Wizard of Frobozz
• Zork III: The Dungeon Master
• Enchanter
• Sorcerer
• Deadline
• Starcross
• Suspended
• The Witness
• Infidel
• Cutthroats
• The Hitch-Hiker's Guide to the Galaxy

Asgard Software

• Ballyhoo
• Hollywood Hijinx
• Leather Goddesses of Phobos
• Spellbreaker
• Suspect
• Wishbringer

http://www.mocagh.org/loadpage.php?getcompany=infocom&npp=25&whatsnew=0&start=0&series=TI-99%2F4A+Asgard+Releases