This is a full port of Marathon 1 to the Aleph One engine. It contains the 27 original solo levels, the 10 original net levels, plus several bonus (solo) levels... 18 original music tracks. Requires Aleph One.
A shapes shuttle that contains M2 wall textures (and M2 landscapes); install this into a spare Shapes file, and you can play M2 maps in Aleph One with their original textures. Very simple... very useful. (Scenery is not included... but this shouldn't be a huge deal.)