I was messing around in MAME last night and ended up finding a killscreen on the popular Bally Midway game Satan's Hollow
Once you reach 1349 flags the game will not spawn any more stages or enemies so the player is stuck in limbo without any way to collect bridge pieces and no way to die!
Reaching this stage would be an absolutely monumental feat however with the right strategies I dont think this is unobtainable (for reference, Ben Falls' 51m WR game was 3.5 hours and reached 789 flags)
Video of the last stage:
:)
Technically it isn't a killscreen because you don't die.
It's a hellscreen
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