I did this run on a Powerpak. In case it matters for future reference, I used a ROM with checksum 7bb417bc023f48cf6184d9bc6b7e87f5.
For information about speedrunning Dragon's Lair and to get a better understanding of what's going on in this run, go to the guide in the SDA knowledge base (referred to as sdakb in my comments below):
I've been wanting to see a speedrun of this version of the game for a long time. This version has a terrible reputation, which is well deserved. The game runs at 12 fps and feels very, very clunky. The levels are pretty relentless in a casual first-time playthrough, but aren't particularly hard once the level layouts have been memorized. The last fight, against Singe, is however both challenging and super RNG-dependent. Anyway, a simple to execute game like this that was basically just a bit of grinding for good RNG was what I was looking for as a distraction during my Adventure Island attempts.
I'll comment here on noteworthy events of this particular attempt. For more detailed level comments, refer to the guide in the sdakb linked above.
I got a "neutral" Lizard King appearance. The LK saves 2.5 seconds by avoiding the gold countdown at the end of the level, so I always reset if I didn't get any encounter in this level. There is a potential additional time gain of a little over a second by the LK despawning one of the enemies, but that's relatively uncommon and not something I required for continuing.
It's possible to get a LK encounter in the dark section. I estimate that the chances are in the range 10-15% and was not something I reset over. Besides, when the LK appears, it messes up the boss fight and requires a different (and slightly slower) approach, which I for some reason have a bad success rate with. 2.5 more seconds could be gained though.
* Since all the platforms in this level are on a global timer, the level is basically on a fixed timer until the pit with the two moving platforms.
* My health was good, so I could avoid the second E (and the accompanying G). That's pretty standard though.
* Sadly, I made a huge mistake at the boss. I released the jump button too early when trying to buffer the second jump. This cost me 1.5 seconds. There is also the possibility of an additional 2 seconds gained by crazy luck against the Reaper. See the sdakb for details.
* With very good luck, the Lizard King can despawn baby dragon(s) by appearing in the right place, which can save up to 5 seconds. I got a LK appearance, but unfortunately not in a place where it saved any time. Most of the time, attempts in level 4 end from the LK appearing in the wrong spot, messing up the baby dragon patterns. The LK can also frequently lead to time losses by appearing in the wrong spot. All in all, getting "neutral" luck is actually pretty good.
* It's possible to squeeze out a few more frames here and there by being more aggressive against the baby dragons. They often manage to throw a fire ball right before dying though, which is the reason for the momentarily hesitations in a few places.
* The Singe fight was sick. Absolutely sick... This was the second best fight for me. Ever... And that includes save state practicing... To get a fight like this in a somewhat decent attempt trumps all the other luck factors and execution mistakes since so much time goes into this fight.
* Jumping forward on the last attack jump is risky. It can sometimes be tricky to know exactly how much health Singe has left, especially if any baby dragons have blocked some of your shots. The jump also needs to be correctly timed with regards to the baby dragons. If one appears during the jump, there is no way to take it out. Usually, I only attempt this jump if I know there is only one jump attack left and that the previous baby dragon has been taken out just before. Of course, that requires that Singe decides to blow a low puff at the right time... So that's a pretty fortunate time saver that I got to include on top of an already very good fight.
* Very often, Singe manages to blow a final smoke puff before succombing. If you don't dodge it, you'll get hit and the fight is over. One more movement frame (= 5 actual frames) and Singe would have had the time to blow a last puff at the end. That was too close of a call to make there and then and decided to dodge a possible smoke puff, which cost me one second.
While none of the possible RNG events before Singe was favorable and there was even an ugly execution mistake, the exceptional Singe fight makes up for it all.
This time is obviously possible to beat though. My sum of best is 9 seconds faster. And the SoB could still go down by at least around 5 seconds in levels 3 and 4 with the best possible RNG. The chances of getting those rare events to line up together with a good Singe fight would require a lot of dedication though.
There wasn't really any resources for the US-version when I began speedrunning this game. The JP- and PAL-versions are so different, that many areas have to be approached differently. I still managed to pick a few ideas from KartSeven's run and the TASes by meshuggah and by Kirkq though.