Displaced Gamers’ Behind the Code series is back, with an under-the-hood look at another NES Capcom game, following their examinations of Ghosts & Goblins and Strider, links are to our previous pointers to their peerless product.
G&G was implemented by popular early NES anonymous developer and target of player recrimination Micronics, but Commando can’t use them as an excuse, as it was developed in-house at Capcom. They were still learning the ropes of the NES at the time (Strider has no such excuse), and it shows. Displaced Gamers thinks that the game was shipped while the programmers were still working on optimizing it. As they do sometimes, DG implemented their own optimizations, improving the game substantially. You can see the product of their work in a 31-minute video they made about it, here. There is a substantial amount of 6502 assembly code involved, but if you skip around I think you might be able to get the gist of why the glitches happen, and how Displaced Gamers fixes them.
As was often the case with your jankier NES games, the scroll stutters and character chaos were caused by the game failing to make its VBLANK timing targets. Thing is, despite the glitches, NES Commando is arguably the best version of the game! Characters sometimes disappear from the screen and backgrounds turn into garbage, but there’s so many cool secrets and things to find in it that I can forgive Capcom for it.
Note that Displaced Gamers doesn’t release patches with their fixes, preferring to focus on making videos. Their code is presented on-screen though, so it’s possible for others to insert the changed programming on their own. I hope someone does this soon, as a fixed version of NES Commando would be nice to play.
