I'm interested in researching and running a 100% Prisoners category for Metal Slug 1.
Unfortunately, I'm not able to find a definitive list of rescuable prisoners, or even a total.
The closest thing I can find is this 5-year old video claiming it's **90 ** and the comments are full of people pointing out prisoners that were missed.
There's also this 21 year old forum post claiming there are a total of 105 but there's no proof or explanation. http://www.neo-geo.com/forums/index.php?threads/metal-slug-question-recaptured-prisoners.54061/post-650936
Can anyone help me out here?
104 afaik is the highest number you can get in single-player.
The POWs that drop down from the trees in the later part of Mission 3 seem to drop at random.
Extra POWs will appear if there are 2 players on-screen. The earliest example can be seen here:

Hi!
I'm Gemant ZBL-Fukuda, I wrote everything related to metal slug gameplay on the neo-geo.com forums. A speed run with all 106 prisoners is impossible due to some of them appearing at random. In particular, in stage 6 there are 2 random prisoners exceptionally rare.
This is a complete list for Metal Slug 1:
stage 1: total prisoners: 10, hidden: 4
stage 2: total prisoners: 12, hidden: 3
stage 3: total prisoners: 17, hidden: 4 (4 random)
stage 4: total prisoners: 23, hidden: 11
stage 5: total prisoners: 15, hidden: 5
stage 6: total prisoners: 29, hidden: 7 (3 random)
Can anyone find evidence of a higher number than 104?
the two missing prisoners are hidden in the large boulder at the beginning of stage 6. The spawn rate is less than 0.5%.
Hello everyone, we apologize for any inconvenience caused these past few days. Everything is back to normal, as it was before, for the "Overclock" and "Other" categories.
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