I'm not sure what level it is (it's one or two levels into the underground factory area), but I'm stuck trying to find the keycard for this level. I've looked in every inch of the level and tried everything i can think of (blowing up walls, boxes, etc.), but I cannot find it anywhere. I have already found the Bomb-Babe beyond the initially-locked doorway.
Some descriptors for the level in question:
- Pretty much all walkways (not solid floors)
- An elevator leading up to the doorway you need the card for right near the start
- The key needed is a red one
- There's a several moving walkways (moving parts of a walkway), one of which has indestructible crates that move across it and GLOPP (green stuff) underneath
- There's a Double Damage powerup (that I have not acquired yet) on a coinciding walkway in the background near the start

I guees you're talking about Manhattan Project... lucky you who can play it after the chopper boss.

So you get it from killing the robot?
That's odd. It never spawned for me...