Prince of Persia in 15 Minutes

[davidn]

http://www.youtube.com/watch?v=ruw81L7aXCs

In tribute to the great people at AGDQ this year, here is the only game that I've ever made an attempt at speedrunning - it's Prince of Persia on the PC. I used to play this all the time a few years ago, trying to take seconds off my time... but I hadn't played it since 2006 and a whole plethora of new techniques have been discovered since then, making my time look unimpressive in comparison. So to do something a little different, here I attempt to get to the game's end in the practice mode, which reduces your timer to 15 minutes so that - theoretically - you can't complete the game.

This is without a doubt the most exhausting video I have ever produced.

Comments

[davidn]

I just checked the credits again and the programmer is listed as Lance Groody! Jordan Mechner is listed as "director", so presumably had some sort of supervising role. Nevertheless, we also have to thank Lance for caring about it enough to actually make it decent. The Apple II version really is... uncanny - it has a bit of slowdown when more than one object is moving on the screen, but it feels so much more responsive than you would expect from a machine of that age, especially when compared to the previously mentioned awful ports to much more powerful consoles of the time.

This run uses only the techniques that I knew about at the time, but I looked up the current state of speedrunning the game in between doing the run and commenting on it, so there are a couple of places where I knew that I could have done better. As far as I remember, the last time I played I was two seconds off the world record, but that's been smashed now - and I never managed it all the way through in one continuous run, I'd always do it in multiple segments, saving and retrying each level until I got the fastest time I possibly could in each one.

The mouse section confused me so much when I first played this, I remember - it's the only point in the game in which you're in an impossible situation and have to wait for something to happen, so it's very easy to assume that something's gone wrong and to restart without seeing the mouse. You can always make a level unwinnable by falling off a loose tile at the wrong time, but at least then you know that you've done something wrong - the use of the tiles is usually very obvious. No actual glitches are used to bypass the mouse section - it's just that the amount of time needed to get to the exit switch and back isn't quite as long as Jordan Mechner thought if you really scream back and forth (the biting gates are meant to dissuade you from this) and it's just, just possible to get out. Some other console ports - probably the SNES one - actually extended that section so that you really couldn't get back in time.

At 11:32... if you go down the left hand side, you can't get to your feet quickly enough to escape the guard, and a sword swipe when you don't have your own sword out is instant death. There is some workaround to that where if you jump into the left wall at the right angle, you'll bump against it on the way down and will be on your feet when you land, and therefore safe. I don't think I ever successfully did it!

The bug I'm really interested in is the teleport on level 12, because I've never really heard a satisfactory explanation for it - http://www.popot.org/documentation/images/Integer_overflow_bug.png shows a diagram, but it doesn't explain why it happens in only this location - perhaps it's about clinging on to a platform that's just on the edge of a new screen?

The cutscene is usually the princess standing at the hourglass - but if you've got very little time left, she's standing away from it at the right hand side, you hear the sound of a door opening, and she turns around...! I hadn't seen this before as I'm used to reaching level 12 with about 45 minutes left - it's a nice touch, very much in character for this game :)

Perhaps I'll do another run soon with what I've learned since this video! And I'll keep the obscenity track just in case ;)

[ravenworks.livejournal.com]

Oh, shoot! I didn't have the context to appreciate the nature of that teleport until I saw the map in that overflow bug explanation! I thought those two screens were horizontally adjacent, and you only 'teleported' up by a single tile!!

From what they're saying in the thread 'linked' in the image, it actually CAN be used other places -- it's just that none of those other places happen to be useful for speedruns, I guess?

And oh gosh, wow -- the door opening, that's scary even to read about! Making the race even more pulse-pounding :) (I almost feel like he shouldn't have saved it for only if you're that close... then again, I guess most folks WOULD be that close, and it being different with MORE time is the easter egg rather than the other way around!)

It feels so strange to me that he's not making games any more....! Even if he's also good at writing, and drawing, and his other passions, it's like.... there are other good writers and painters, and so few good programmers :D It's like one of the Beatles giving up music to get into gardening or something. (But, then again.... life is to be enjoyed! Here I am, so obsessing over productivity that I'm projecting it onto someone else and insisting that they should do what they're good at instead of what they love..... it's a hard mindset to shake sometimes!)