I don't know if he mentions it in this video but one of my favorite parts of Robotron lore is that they had a bug in the movement code for Enforcers, which were

I don't know if he mentions it in this video but one of my favorite parts of Robotron lore is that they had a bug in the movement code for Enforcers, which were supposed to just float towards the player. There was some type of overflow bug which would cause some of them to hug one end of the screen for awhile and then quickly dart to the other side, and it ended up making them more difficult so they left it in.