There's a RetroAchievements leaderboard for Oddysee called Kill 'Em All: "kill as many Mudokons as possible and finish the game". Most people top out at 87. The best anyone managed was 89, and it stood there for five years. The tool-assisted "maximum casualties" run gets 93 (with glitches), frame-perfect, no human doing that.

All of those answer the question "how many unique Mudokons can you actually reach and kill?" And they're all under the 99 the game ships with.

I got interested in a different question: how high can the counter itself go?

The known trick, in reverse

The famous exploit is the Mudokon count glitch: you push rescues past the game's 99 limit by saving the same Mudokons over and over. It's documented everywhere. But I couldn't find a single person who'd tried it the other way round.

There's probably a reason for that. The three Mudokons that make rescue-farming easy are standing together in the Scrabanian Temple, safe, convenient - but completely unkillable from where you stand! The one Mudokon you can kill over and over is one door away, alone, sharing a room with a Scrab. The famous glitch grew where the game made it convenient. I think nobody went looking in the awkward room.

The lone respawning mudokon being shredded by the Scrab

Eight hours

So I sat in the awkward room and killed the same Mudokon until my thumbs gave out. Every single cycle was an absolute slog. Starting from this specific door in the Scrabanian Temple, I headed inside, dodged the Scrabs and climbed up to the hidden area to jump through a bird portal. There, I’d trick the poor mud into walking off a ledge to be shredded by the Scrab below. But the kill was only half the work. I still had to survive back to the start of the path, exit out to the Temple, walk into a different door just to force the game to save the state, and then back. I did this over 200 times.

Eight hours later, I wrapped up my business in the Scrabanian Temple and returned to RuptureFarms. The counter read 255. The next kill wrapped it straight back to 0.

LCD status board reading -15 / 255

Where it falls apart

255 isn't really the answer, because the game stops letting you finish long before that.

The LCD status board computes Employees = 99 - casualties - escapees. In the TAS video above that's 99 − 93 − 1 = 05, and it renders perfectly. But the font code only reserves room for 3 characters. The moment that number reaches -100 it's four characters wide, and the fourth glyph gets written into memory it doesn't own; right over the header of the next block on the resource heap. The GPU hangs.

That's why my board says "-15" employees at 255 kills: 99 − 255 − 1 = −157, and the stray "7" wanders off to wreck things.

So the game doesn't break because you killed too many Mudokons. It breaks because the number got too wide! And only at the exact instant a status board is drawn on screen. In the temple you can farm forever. It's Return to RuptureFarms, where the boards live, that ends the run.

The answers, depending on what you're asking:

• 89 — most unique Mudokons killed by a human, and the leaderboard record for five years
• 93 — most unique Mudokons killed (tool-assisted, glitched)
• 197 — highest count where the board still renders cleanly (99 − 197 − 1 unavoidable rescue = −99, exactly three characters)
• 203 — the most I could reach the end credits with
• 255 — as high as the counter itself will go, but you're not finishing that run

203 out of 99 Mudokons. xD

Maximum 203 casualties without the game freezing before reaching the end