K240 should have null modem multiplayer, like Populous. I always thought it'd be cool if you had a human opponent, but his ships and buildings looked alien to you.
I read in an interview that multiplayer was originally on the design documents, but they couldn't do it on time. I wonder if it was too difficult for K240? You had a lot of data to track (24 asteroids, 100 buildings per asteroid, 700 ships and however many missiles, per tick), and that might have been too much for a null modem cable to handle.