This is an unfinished Fort Apocalypse clone. The archive contains two disks,
showcasing two different versions (read: levels) of the game. FORTDEMO.ADF is
the one you want to run, FORT_MFM.ADF features another level but has collision
detection turned off.

Found on the author's website, uploaded with kind permission from Chris
Leathley.

http://members.iinet.net.au/~cleathley/gamehistory.html

Archive:  /home/aminet/aminet_root/doc//game/shoot/Fortress.zip
 Length   Method    Size  Cmpr    Date    Time   CRC-32   Name
--------  ------  ------- ---- ---------- ----- --------  ----
  901120  Defl:N   452261  50% 2017-06-12 09:35 8e8ae73f  FORTDEMO.ADF
  901120  Defl:N   327592  64% 2017-06-12 09:35 3ece9f2a  FORT_MFM.ADF
--------          -------  ---                            -------
 1802240           779853  57%                            2 files