'It's DOOM, but You Can Cut, Copy and Paste Opponents'

From the Adafruit blog:

Greg Technology (aka Greg Sadetsky) on YouTube demonstrates a version of Chocolate Doom where opponent characters can be cut, copied, and pasted at will to add a bit more fun to the game.

Obviously this means you can paste in your attackers multiple times. ('They're kind of not really happy if you do that...' Greg says at one point in the video. 'But then, you can also cut them... like, vaccuum them out.')
In response to a comment on YouTube, Sadetsky explained that 'It stores a reference to the kind of monster (every monster has a unique type number).

'So yeah, you could paste them across games!'

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