Repton 3 - Discussion and Level Codes

colinmacc

Harry-Wood wrote:
You may notice the last three levels are a little bit easier than level 5 (in both “easy” and “main”). This is because in my version, as in the original, it will disable the map on the last three levels, which of course makes it much harder. I make the puzzles a little different, and generally a little easier for those. I also put in a design quirk on the last two levels. Large areas of brick walls. This a slightly weird idea in retrospect, but the idea was to create a “fake edge” causing a surprising moment for the player. In the absence of a map, you realise you're not sure where the edge of the map is! The effect doesn't work here since the map is available.

In my game download the levelsets are “locked”. I was trying to prevent cheating, so that you have to play through discovering the password for each map in turn. Also so that you can't view the map on those last three levels by simply opening it in the editor (or edit the maps to cheat for that matter). I guess the “locked” file format created an obstacle for bringing my map designs here! But it's quite funny really. My naive younger self understood “encryption” to mean scrambling up the file format algorithmically as much as possible, but let this be a lesson to everyone. You should never “roll your own encryption”! Clearly this was more obfuscation than proper encryption, and was wide open to some known-plain-text codebreaking. That still must've been a painstaking process mind you. Did you do that yourself?… or I see Generald J Holdsworth published a “Repton Map Decoder” software and even a detailed PDF laying out all my attempted obfuscations. Amazing!

You know I actually started work on designing a “hard” levelset. I wonder if I can dig out that half-finished file somewhere.

I'm not sure I did notice that about the levels, but I can disable the maps for the last 3 levels in each set if it makes it more authentic! I might have guessed at some of the level times too. Yeah I used Gerald's decoder to extract the level data, and I wrote another scratch project (not shared) which converted it into the format I needed.

EDIT: Oh, and if you have any more levels of course I'd be interested

Last edited by colinmacc (Aug. 21, 2025 10:36:07)

Harry-Wood

There's also a couple of differences from the original which are my fault. I created my game purely from memory of playing Repton in the 80s and there's a couple of things I misremembered. Firstly, I made the maps a bit bigger than the original. 31x31 vs the original 28x24 I think. So I guess that meant you had to make your version cater for different map sizes. What a pain!

Secondly, an interesting little detail: Do rocks fall off time capsules? I misremembered this. I thought not, and coded my game to make them “flat”, but I saw that you have them sliding off, and when I went to check the original I see that you were correct. Although that's a small detail, of course it effects the puzzles. For example Level 5 on the “main” set (the hardest of these maps), has three time capsules where the map puzzle design assumes they'll hold a rock. Since they cannot, I think the level is not possible without losing a life. I think we could solve this by swapping time capsules for earth instead.

colinmacc

Harry-Wood wrote:
There's also a couple of differences from the original which are my fault. I created my game purely from memory of playing Repton in the 80s and there's a couple of things I misremembered. Firstly, I made the maps a bit bigger than the original. 31x31 vs the original 28x24 I think. So I guess that meant you had to make your version cater for different map sizes. What a pain!

Secondly, an interesting little detail: Do rocks fall off time capsules? I misremembered this. I thought not, and coded my game to make them “flat”, but I saw that you have them sliding off, and when I went to check the original I see that you were correct. Although that's a small detail, of course it effects the puzzles. For example Level 5 on the “main” set (the hardest of these maps), has three time capsules where the map puzzle design assumes they'll hold a rock. Since they cannot, I think the level is not possible without losing a life. I think we could solve this by swapping time capsules for earth instead.

Your memory is excellent!

So it's been a few years since I did this, but your observation about the time capsules… I must have known about that, because on the final level of the Main set, in my engine some rocks would immediately slide off the time capsules from their starting positions, which did make that level impossible. And to solve that problem I did as you suggested, which was to replace those particular time capsules with dirt.

But it's very interesting that I didn't change anything on level 5…. because I must have been under the impression it was still solvable even with that rule, and actually I'm pretty sure I've had it confirmed by at least 2 other people, so it might be there is still a way to solve it. But yes I can't guarantee that they did it without losing a life, and unfortunately I don't have time at the moment to work out how to solve it again

(it's a shame it's not level 4 - I've a youtube video of me solving that as I was pretty proud of working it out at the time!)

The different map sizes weren't a huge problem as it's encoded into the level string. There are quite a few little quirky behavioural differences between the different versions of Repton, for example sometimes broken eggs roll off curved edges and sometimes they don't, and in Repton 2 you can run through a broken egg but you can't do that in any other version, etc. and I'm really not sure I've got the fungus calculation right at all!

colinmacc

Harry-Wood wrote:
Secondly, an interesting little detail: Do rocks fall off time capsules? I misremembered this. I thought not, and coded my game to make them “flat”, but I saw that you have them sliding off, and when I went to check the original I see that you were correct. Although that's a small detail, of course it effects the puzzles. For example Level 5 on the “main” set (the hardest of these maps), has three time capsules where the map puzzle design assumes they'll hold a rock. Since they cannot, I think the level is not possible without losing a life. I think we could solve this by swapping time capsules for earth instead.

I found a couple of comment threads in the project you might be interested in, from 3 years ago, when myself and the amazing “ScratchBoyBob” were play-testing all the levels..

https://scratch.mit.edu/projects/567711434/#comments-225319280

https://scratch.mit.edu/projects/567711434/#comments-225651416

https://scratch.mit.edu/projects/567711434/#comments-226129389

So these do confirm that we knew about the difference in the behaviour of the time capsules, and I identified and changed some parts of some levels which were impossible because of that, but again, not level 5, which we both agreed was still possible to do.

(There was also some discussions about the starting direction of some of the spirits, which is also not consistent through all variants of Repton 3)

Last edited by colinmacc (Aug. 21, 2025 13:31:34)

Harry-Wood

heehee! So funny to see you puzzling over the exact same thing

"I changed the top left of MAIN 5 last night because I thought it was impossible, but I’ve just looked again and I think it is possible just harder than it was meant to be, so I’ll put it back"

Yeah that top left bit. I was so sure that the time capsule issue made it impossible …but looking at it again

28#24#0#9999#1##AEEHGGGGGGGGGGGGGGGGGGGGGGGGBBBGFGGGGGGGGGGGGGGGGGGGGGGGEGMGHGGGGGGGGGGGGGGGGGGGGGGGAGHGHGGGGGGGGGGGGGGGGGGGGGGGEBAGHGGGGGGGGGGGGGGGGGGGGGGGBAHGHGGGGGGGGGGGGGGGGGGGGGGGBAGGHGGGGGGGGGGGGGGGGGGGGGGGGHNGBHGGGGGGGGGGGGGGGGGGGGGGGGHGHGGGGGGGGGGGGGGGGGGGGGGGHGGHHGGGGGGGGGGGGGGGGGGGGGGGG_GGGGGGGGGGGGGGGGGGGGGGGGGGGGG\GGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGG

It is possible!

Last edited by Harry-Wood (Aug. 22, 2025 14:42:15)

colinmacc

Harry-Wood wrote:
heehee! So funny to see you puzzling over the exact same thing

"I changed the top left of MAIN 5 last night because I thought it was impossible, but I’ve just looked again and I think it is possible just harder than it was meant to be, so I’ll put it back"

Yeah that top left bit. I was so sure that the time capsule issue made it impossible …but looking at it again

28#24#0#9999#1##AEEHGGGGGGGGGGGGGGGGGGGGGGGGBBBGFGGGGGGGGGGGGGGGGGGGGGGGEGMGHGGGGGGGGGGGGGGGGGGGGGGGAGHGHGGGGGGGGGGGGGGGGGGGGGGGEBAGHGGGGGGGGGGGGGGGGGGGGGGGBAHGHGGGGGGGGGGGGGGGGGGGGGGGBAGGHGGGGGGGGGGGGGGGGGGGGGGGGHNGBHGGGGGGGGGGGGGGGGGGGGGGGGHGHGGGGGGGGGGGGGGGGGGGGGGGHGGHHGGGGGGGGGGGGGGGGGGGGGGGG_GGGGGGGGGGGGGGGGGGGGGGGGGGGGG\GGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGG

It is possible!

Yes!
That's what I love about Repton - there's quite often more than one way to solve a problem

Going back to the spirits, I distinctly remember now in order to get some of them to go in the right direction initially on your levels I had to be a bit creative with their starting positions, so they may look at bit different to how you remember them. But once they're going the right way, they should behave as you'd expect!

J__cat

ScratchMario3000 wrote:
J__cat wrote:
you have to run away from the monsters.

28#24#0#9999#1##PYYYYYYYYYYYYYYYYYYYYYYYYYYO_CCCCCCCCCCCCCCCCCCCCCCCCCCGKKKKKKKKKKKKKKKKKKKKKKKKKKNG\IHLLLLLLLLLLLLLLLLLLLLLLLPG^IJGGGGGGGGGGGGGGGGGGGGGGGGGBIJGGGGGGGGGGGGGGGGGGGGGGGGGBIJGGGGGGGGGGGGGGGGGGGGGGGGGBIJGGGGGGGGGGGGGGGGGGGGGGGGGBIJGGGGGGGGGGGGGGGGGGGGGGGGGBIJGGGGGGGGGGGGGGGGGGGGGGGGGBIJGGGGGGGGGGGGGGGGGGGGGGGGGBIJGGGGGGGGGGGGGGGGGGGGGGGGGBIJGGGGGGGGGGGGGGGGGGGGGGGGGBIJGGGGGGGGGGGGGGGGGGGGGGGGGBIJGGGGGGGGGGGGGGGGGGGGGGGGGBIJGGGGGGGGGGGGGGGGGGGGGGGGGBIJGGGGGGGGGGGGGGGGGGGGGGGGGBIJGGGGGGGGGGGGGGGGGGGGGGGGGBIJGGGGGGGGGGGGGGGGGGGGGGGGGBIJGGGGGGGGGGGGGGGGGGGGGGGGGBIJGGGGGGGGGGGGGGGGGGGGGGGGGBIJGGGGGGGGGGGGGGGGGGGGGGGGGBOPGGGGGGGGGGGGGGGGGGGGGGGGGBBBBGGGGGGGGGGGGGGGGGGGGGGGG

(also, can you add badly drawn repton to the repton games list on your first comment (unless you can't edit comments)).
I can't win the level because it requires you to kill the enemies, and there isn't a clear way to do so.
You might be able to remove the bomb, which I think makes it so in order to win you need to collect all diamonds.

I did, here's the new level:

28#24#0#9999#1##PYYYYYYYYYYYYYYYYYYYYYYYYYYO_CCCCCCCCCCCCCCCCCCCCCCCCCCGKKKKKKKKKKKKKKKKKKKKKKKKKKNGBIHLLLLLLLLLLLLLLLLLLLLLLLPGBIJGGGGGGGGGGGGGGGGGGGGGGGGGBIJGGGGGGGGGGGGGGGGGGGGGGGGGBIJGGGGGGGGGGGGGGGGGGGGGGGGGBIJGGGGGGGGGGGGGGGGGGGGGGGGGBIJGGGGGGGGGGGGGGGGGGGGGGGGGBIJGGGGGGGGGGGGGGGGGGGGGGGGGBIJGGGGGGGGGGGGGGGGGGGGGGGGGBIJGGGGGGGGGGGGGGGGGGGGGGGGGBIJGGGGGGGGGGGGGGGGGGGGGGGGGBIJGGGGGGGGGGGGGGGGGGGGGGGGGBIJGGGGGGGGGGGGGGGGGGGGGGGGGBIJGGGGGGGGGGGGGGGGGGGGGGGGGBIJGGGGGGGGGGGGGGGGGGGGGGGGGBIJGGGGGGGGGGGGGGGGGGGGGGGGGBIJGGGGGGGGGGGGGGGGGGGGGGGGGBIJGGGGGGGGGGGGGGGGGGGGGGGGGBIJGGGGGGGGGGGGGGGGGGGGGGGGGBIJGGGGGGGGGGGGGGGGGGGGGGGGGBOPGGGGGGGGGGGGGGGGGGGGGGGGGBBBBGGGGGGGGGGGGGGGGGGGGGGGG

J__cat

Have you seen my Scratch Cat remix of Repton? it's Repton 3, but with scratch cat as a player and (almost) all the graphics I added are from Scratch's costume library or made by me. https://scratch.mit.edu/projects/1206785950

Last edited by J__cat (Aug. 29, 2025 01:29:12)

colinmacc

J__cat wrote:
Have you seen my Scratch Cat remix of Repton? it's Repton 3, but with scratch cat as a player and (almost) all the graphics I added are from Scratch's costume library or made by me. https://scratch.mit.edu/projects/1206785950

Cool!

d0rc0

can these maps be ran in badly drawn repton without any problems?

colinmacc

d0rc0 wrote:
can these maps be ran in badly drawn repton without any problems?

Yeah it's the same game engine

d0rc0

colinmacc wrote:
d0rc0 wrote:
can these maps be ran in badly drawn repton without any problems?

Yeah it's the same game engine

ah thank you!
as i tried one of the much earlier ones and go stuck

glad to know it was just my lack of skill hehe

Harry-Wood

I just wrote a blog post here: https://harrywood.co.uk/blog/2025/09/08/repton-puzzles-and-broken-encryption/ about your scratch version of the game, and the whole funny history of other things. I should contact Gerald Holdsworth too.

Last edited by Harry-Wood (Sept. 9, 2025 09:13:20)

colinmacc

Harry-Wood wrote:
I just wrote a blog post here: https://harrywood.co.uk/blog/2025/09/08/repton-puzzles-and-broken-encryption/ about your scratch version of the game, and the whole funny history of other things. I should contact Gerald Holdsworth too.

Ahh that's great!
Yeah I don't know how Gerald managed to work that out, I couldn't have done that!

colinmacc

Harry-Wood wrote:
I just wrote a blog post here: https://harrywood.co.uk/blog/2025/09/08/repton-puzzles-and-broken-encryption/ about your scratch version of the game, and the whole funny history of other things. I should contact Gerald Holdsworth too.

Yes! I got your 16 bit repton exe to run in 64 bit windows 10! See my reply to your latest comment on your site

J__cat

Harry-Wood wrote:
heehee! So funny to see you puzzling over the exact same thing

"I changed the top left of MAIN 5 last night because I thought it was impossible, but I’ve just looked again and I think it is possible just harder than it was meant to be, so I’ll put it back"

Yeah that top left bit. I was so sure that the time capsule issue made it impossible …but looking at it again

28#24#0#9999#1##AEEHGGGGGGGGGGGGGGGGGGGGGGGGBBBGFGGGGGGGGGGGGGGGGGGGGGGGEGMGHGGGGGGGGGGGGGGGGGGGGGGGAGHGHGGGGGGGGGGGGGGGGGGGGGGGEBAGHGGGGGGGGGGGGGGGGGGGGGGGBAHGHGGGGGGGGGGGGGGGGGGGGGGGBAGGHGGGGGGGGGGGGGGGGGGGGGGGGHNGBHGGGGGGGGGGGGGGGGGGGGGGGGHGHGGGGGGGGGGGGGGGGGGGGGGGHGGHHGGGGGGGGGGGGGGGGGGGGGGGG_GGGGGGGGGGGGGGGGGGGGGGGGGGGGG\GGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGG

It is possible!

I was looking at this and at first I thought there was no way to finish without getting soft-locked, but then like 30 minutes later I finally figured it out! The solution definitely isn't very obvious at first!

waokdaeok

try this out
28#24#0#90#0##`GG_GGGGGGGGGGGGGGGGGGGGGGGGHHHHHHHHHHHHHHHHHHHHHHHHHKNGGGGGGGGGGGGGGGGGGGGGGGGGGGJGGMKHHHHHHHHHHHHHHHHHHHHKNGHGGIGGGGGGGGGGGGGGGGGGGGGGJGHGGHGMKHHHHHHHHHHHHHHHHKNGHGHGGHGIGGGGGGGGGGGGGGGGGGJGHGHGGHGHGMKHHHHHHHHHHHHKNGHGHGHGGHGHGIGGGGGGGGGGGGGGJGHGHGHGGHGHGHGMKHHHHHHHHKNGHGHGHGHGGHGHGHGIGGGGGGGGGGJGHGHGHGHGGHGHGHGHGGHHHHHHHGXGHGHGHGHGGHGHGHGHGHHGGGGGGGHGHGHGHGHGGHGHGHGHGHGGG\GGGGJGHGHGHGHGGHGHGHGHGHHHHHHHHLPGHGHGHGHGGHGHGHGIGGGGGGGGGGGGJGHGHGHGGHGHGHGOLHHHHHHHHHHLPGHGHGHGGHGHGIGGGGGGGGGGGGGGGGJGHGHGGHGHGOLHHHHHHHHHHHHHHLPGHGHGGHGIGGGGGGGGGGGGGGGGGGGGJGHGGHGOLHHHHHHHHHHHHHHHHHHLPGHGGIGGGGGGGGGGGGGGGGGGGGGGGGJGGOLHHHHHHHHHHHHHHHHHHHHHHLPGGGGGGGGGGGGGGGGGGGGGGGGGGGGG

colinmacc

waokdaeok wrote:
try this out
28#24#0#90#0##`GG_GGGGGGGGGGGGGGGGGGGGGGGGHHHHHHHHHHHHHHHHHHHHHHHHHKNGGGGGGGGGGGGGGGGGGGGGGGGGGGJGGMKHHHHHHHHHHHHHHHHHHHHKNGHGGIGGGGGGGGGGGGGGGGGGGGGGJGHGGHGMKHHHHHHHHHHHHHHHHKNGHGHGGHGIGGGGGGGGGGGGGGGGGGJGHGHGGHGHGMKHHHHHHHHHHHHKNGHGHGHGGHGHGIGGGGGGGGGGGGGGJGHGHGHGGHGHGHGMKHHHHHHHHKNGHGHGHGHGGHGHGHGIGGGGGGGGGGJGHGHGHGHGGHGHGHGHGGHHHHHHHGXGHGHGHGHGGHGHGHGHGHHGGGGGGGHGHGHGHGHGGHGHGHGHGHGGG\GGGGJGHGHGHGHGGHGHGHGHGHHHHHHHHLPGHGHGHGHGGHGHGHGIGGGGGGGGGGGGJGHGHGHGGHGHGHGOLHHHHHHHHHHLPGHGHGHGGHGHGIGGGGGGGGGGGGGGGGJGHGHGGHGHGOLHHHHHHHHHHHHHHLPGHGHGGHGIGGGGGGGGGGGGGGGGGGGGJGHGGHGOLHHHHHHHHHHHHHHHHHHLPGHGGIGGGGGGGGGGGGGGGGGGGGGGGGJGGOLHHHHHHHHHHHHHHHHHHHHHHLPGGGGGGGGGGGGGGGGGGGGGGGGGGGGG

ahh nice one! Weirdly frightening chase!

d0rc0

uggg
stuck on CrabPuzzle

Is there any tips/walkthroughs

GrayCat144

Here's my level. It's possible but very hard to complete with 0 deaths. Good luck!

28#24#2#120#0#oveq#1#22#23#19#11#0#7#5#DCABAWWCDCD]DCWBJGGGGGGAGGHHXMKGMWHDHLPGOLLLPGGGGGGKNGHHGIHGOWJCIBGGGGGGGGGGGGGGGGWWGG_GFWJDIGGGGGGGGGBABGGGGGWYFGGGGWJCIGGFGGGGGGRWSGGGGGCMKKKKCWJGIGGGG[GGGGGGGGG[GGGGG`GHCIHKHGGGGGGGGGKKKKKKKKNBGGGWBIJGGGBGGGGGG`GGGGGGAGGGGGGHCIJGGGGGGGGGWWGGGGGGKNGGLBLLDIJGGGGWGGGGWWGGGGGGGGGGGGGGGIJBGFGGGGGGGGGAHGGGGGGGGGGGGIJGWGGGGGGMGNCWGGGGAFGGG\GGGIPGGGBGGFGIGJCIGFYBRSGGGGGGGIBGFGGGGG[IGJCIGRSGQQGGGGABGIBGGGGGGGGIGJCIGQGGGQGGGGKGMHLLLLLLLLGOGJDIGQGGGQGGGGGGOHFCDCFDDCGGGJDIGQGGGQGGWGGGYI^DFCDCFWWWDWDWQQQQQQSGWGGGXIKKKWWWWDDDDWDWQQCCCQGGWGGGGIZBXCCCWDFWWWDWGACGCQGGGGGGHHLLLWFCWDDDDWDDGQCCCQGGNGMBCWCCCCCCFWWWDWWWGTQQQUGGJ]IW`WCFWWWCCCCCCGGGGBBGGGGGHKHBDWCCCEWWWWFWWWWKNBBGGGD[

Last edited by GrayCat144 (Oct. 19, 2025 17:36:07)

Discuss Scratch