I had 200HP in making an insane difficulty run on this level, then the boss decided to teleport himself out of existence... As you can see I'm circling in the empty boss room... The boss is gone.
You cannot hear it's static and cannot find it anywhere in the level, the exit door remains locked. Looks like this is a dead end, it's unwinnable from here.
This happened while recording it, so upsetting, after hours of struggle...
I don't use ingame saves while making these runs, but It seems I'll have to keep a saved state when returning from the secret level, just in case.
Google search didn't say anything about this glitch.
I will download it's source code to learn about the boss behavior, I see a slim chance of recovery here. In D1, bosses teleport randomly in regular intervals to randomize the game a bit. The boss might teleport back into the level, maybe 5-10 minutes later...
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