All right, on a couple of sleepless nights I started mulling over possibilities for a speedrun route, and I think I've got at least parts of a good route worked out. At first I was thinking about going to the bay early to get the match, and about how to manage a trip in and out of the mine. And I tried to keep in mind some things:
There are 7 objects to be taken to the site of Zaks' cloud castle, which means at least 3 trips to that site are required as well as at least 2 trips to the castle proper. In order of use, these items are the shamrock to move the leprechaun, the bean to grow the giant stalk, the winch handle to open the portcullis, the bucket of water to put out the fire, the skull elevator key, the carpet for the nail bed, and the rope to swing to the last corner of the castle. Now, that same rope has 3 required uses altogether: Once to get Dylan's house key, once to get to the trolls' castle's portcullis winch wheel on the pirate ship, and finally in Zaks' castle. Yes, you need to get into Dylan's house even if you don't want to pay for the bean with his cow, because the house contains 2 stars you need. You also need to get kicked off the pirate ship by Captain Blackheart at least once to collect the stars in the pit, and you need to ride the mine cart at least once to collect the stars on the tracks plus the grave-digging spade at the end--so don't ride the cart with 3 items if you intend to collect that spade. The ride is long enough I think it should only be ridden once anyway.
I also came up with a few techniques or tips for speeding up play. For one thing, carrying 3 items can be helpful when you're ready to pick up one item and drop another that you no longer need, because Dizzy will grab and drop in the same action in this situation. Sometimes I worry about something like "But this aqualung isn't close enough to where I need to use it again," but then I remember that if I'm doubling back over that same path anyway, I'll be able to pick up that object in the same amount of time no matter where I dropped it. I'm also looking into ways to optimize the treehouse complex, because that's the roughest part of my plans right now, being so complicated and full of key-juggling. I used to think "Oh, the rope saves me from having to use that elevator key!", but the thing is, an elevator key gets used up, while the rope will stay in my inventory using up space that could have been used to transport a third object. That's also why I think it's a bad idea to get Dylan's cow, because it means running around with that cage and trying to get Pogie to show up on your path at the right time, whereas collecting the coin is easily done while just crossing the bay or collecting its stars. It's also important to know the quickest ways to get back down from the village after you've collected everything you want from it. In some places you want to step down from floor to floor to keep Dizzy from getting stunned by the fall height; in others you may want to jump as far as you can so that you bypass the remaining floors completely and only get stunned once at the end rather than at stops in between. Oh yeah, and transitions to new areas are kinda long in this version, so look for ways you can avoid unnecessarily bumping into the next room when it would waste time, using trick jumps or whatever.
So as I apparently posted three months ago, I decided it would be a good idea to go straight for Blackheart's ship first. Well, maybe some preliminary work is needed before leaving the village, since I plan to re-enter it from the right with a full load of items. So maybe bring Denzil's elevator key to the junction near the carnivorous plant along with the plank, grab the ground elevator key, use the plank, grab the weedkiller, turn on the ground elevator, and kill the plant--possibly with Denzil's elevator key in hand again to place it further along, because I was thinking you could open up Daisy's and/or Denzil's houses then, and then leave the village to the left as you pass Denzil's house or the meeting hall, so that you collect a star in the area where you can use a rope but I may not use it there. (It's just a shame it appears to be impossible to drop directly from Denzil's floor to Daisy's house in this version because of Dizzy's constant high speed, as that would have been a nice shortcut after grabbing Daisy's door key.)
Now we're heading for the ship with an empty inventory. I don't want to bring the rope just yet because the items on the way get used right after they're picked up, so bringing anything would cause a lot more inventory cycling. So we use the meat, use the bag of coins, pick up the rum barrel and crowbar and use the barrel to get onto the ship. Raid the decks of the ship, collecting all their stars, the dynamite, and the cloud castle winch handle with the use of the crowbar. Then do the bubble pit, whatever it takes to manipulate the right bubbles to get you to all the stars and to the top quickly, and end up on the little island at Carber Bay with the dynamite and winch handle in hand.
Exchange the dynamite for the pickaxe on the nearby beach, grab the aqualung, and take a leap into the bay. Use the pickaxe and grab the treasure chest; if you have the items arranged a certain way I imagined, you could swap the winch handle for the chest in a single move, use the pickaxe, jump onto the ship again to reclaim the handle, and ride the next bubble up. Then you should be all ready to exchange the aqualung for the bag of salt, use the chest, use the salt (but have to cycle the handle an extra time, sorry), and exchange the winch handle for the matchstick. Not only does this get us what we need to save Denzil, it also leaves the cloud castle's winch handle almost exactly where we'll need to grab it from next, near the leprechaun! So that's going to make this a 1/3/3 delivery of the 7 items rather than a 3/2/2 distribution as I had expected before.
So grab the aqualung again to take the match back across the bay. (How does it stay dry?) Take the dynamite, exchange the aqualung for the machine wrench, exchange the dynamite for the mushroom, use the wrench on the elevator control machine, and grab GrandDizzy's elevator key. And that's everything we need to take back to the village except for Dozy's cymbals!
And again I'm hazy on the exact order to do the next steps in the village. I know we're here to get the dragon egg from GrandDizzy and the flippers from Denzil, but we have to stop by the meeting hall sometime for GrandDizzy's door key, which means setting down the match so that we can unlock GrandDizzy's elevator and house and bring the first medicine ingredient in one trip, so we'll have to backtrack down one floor to grab the match again to free Denzil. Or we could do it vice-versa, drop the stuff for GrandDizzy in front of the meeting hall, free Denzil, then come back for GrandDizzy's stuff as we drop off the flippers. Also, I'm thinking I want to do something like bring Dora's door key up the path as I'm working on delivering the stuff to GrandDizzy's house, because I want to leave Dylan's, Dora's, and Dozy's floors for the final trip since I've got enough stuff to cart around on this trip already, but I realized rather late that my plan for that trip involves carrying 4 objects up to that part of the treehouse complex: The rope, Dozy's door key, Dora's door key, and the cymbals. So what I thought I might do is, since I need to backtrack for one last GrandDizzy item after activating the elevator anyway, I would drop down from that elevator to land on Dora's door key, carry it over and swap it with the magical star plant so that it's a little closer when I need to go back for it. Heck, I might not even activate the elevator the first time I stand on it; I could drop the mushroom on it, and use the 3-for-1 swaps to get the elevator key in while hanging onto the 3 other items I bring there.
However it's done, the end result is that we leave the treehouse village to the right with the golden dragon egg and flippers for swimming in hand, and we're shortly getting to the part I thought was inspired enough that I decided to try to figure the rest of the plan out. Drop the dragon egg at the mine entrance, pick up the aqualung, and do a circular sweep of Carber Bay, collecting the rest of the stars and the large gold coin. Go back and exchange the flippers and the aqualung for the dynamite and the dragon egg and enter the diamond mine.
Drop the coin at the junction where the mine cart is to the left. Pick up the bridge-builder's axe, use the dynamite and egg to get the gold shamrock, come back and exchange the axe for the coin. Now you'll enter the mine's railway with the shamrock and coin in your possession, collecting all the stars and reaching the final exit to receive the grave-digger's spade. Drop the shamrock, take the coin to the first tunnel to the right, and give it to the shopkeeper for the magic bean. I didn't see any stars in the far tunnel or to the right of that tunnel on either street in this version, so you should be able to use the near tunnel every time. Go back for your shamrock and into the graveyard. Dig up the hole and come out with a bucket filled with water; you could drop your bean and shamrock outside first, but the "3-for-1 swap" might be faster. If you grab the trampette first to minimize item cycling, then you have to drop off the bucket's platform an extra time to fill it, so I'm not really sure what's fastest yet. One nice thing is that you can see when the water has entered the bucket immediately because your score increases for doing it.
Make your way through the graveyard to see Shamus the leprechaun, drop the bucket of water for a moment, give him the shamrock, and plant the bean. Now go a little to the left for the portcullis winch handle we left, grab the bucket again, and now we're ready to enter Zaks' castle for the first time! The order of objects works out too: Open the door with the handle, use the bucket on the fireplace, grab all the stars in that region of the castle, and then it's time to backtrack out of there until we collect some more items. Since I plan to go to the left from here, you can save the far-left clouds with stars on them until you're ready to fall back down. I think we'll have to just double-back from the far-right cloud with a star at some point, though.
See, you can use the mine exit on the right beach to re-enter the mine now, and that puts us right near that axe we left. Take it out the top of the mine, grab the aqualung, and go down that bridge to get that pair of cymbals. Then comes the treehouse village item-juggling that I'm still not sure about... The current idea is that I would end up with Dora the frog, the thick rug, the rope, and all the remaining stars in the village, including the ones in Dylan's house. This might even be the first time we grab the rope. Ah, but it's starting to come together as I type this. See, I discovered that not only can I drop beneath the bottom of Dylan's elevator if I'm quick enough, but I could even manage to turn around and start falling to the right from there. That would be a fairly quick way to get back to Dora's house key, which I had planned to leave in the original location of the star plant. So let's say we start by going up past that part with the pair of cymbals, the rope, and Dozy's door key. Swap one of the non-rope items with Dylan's elevator key and start the elevator (so it won't be stuck at the bottom later, for one thing). While we're here, we might as well go to the right to drop down and collect the one-ton weight. Drop everything but the rope in front of Dylan's house, go to the left, and swing over to get his house key. Fall through the elevator with that special technique I mentioned, go back for Dora's door key, go back up and collect whatever you left in place of Dylan's elevator key. Take the stuff for Dozy--weight, door key, and cymbals--up to his house to get his carpet, then come back for Dora's door key and the rope and grab Dora. I think we want to leave to the left to kiss the prince and re-enter the town, so you could probably walk off from Dora's floor and collect the star above GrandDizzy's house so you're not backtracking from it when you get Dylan's door key, then jump the rest of the way down from there.
But as I think about it, there are other ways you could arrange that scenario. You could swap something for Dora's door key when you first pass it on your way to Dylan's floor, so that you could take it to Dora's house first thing, and later drop from Dozy's floor to the left side of Dora's floor for a quicker exit. Someone will have to play around with this to find out the best way.
Anyway, after meeting with Prince Clumsy, we'll have a rug, a rope, and a crossbow. For a while I was thinking the rug could be taken across the bay on another trip with the flippers, but then I decided it could be weaseled into this next procedure. Take everything to the left into Keldor Town, but leave the carpet beside the first tunnel to Bridge Street. Enter the first tunnel to Dock Street instead so you can board the pirate ship again. Use the rope to swing across the rigging to reach the portcullis winch wheel. Now, we've added another item, but we still need the rope for later, so that's why I left an item behind. We'll have to continue to leave it there until we use the winch wheel and the crossbow to get into the Keldor castle and come out with the bridge kit. Yeah, so that means doubling back across two streets and tunnels to pick up the rug again. In practice the backtracking turned out to be a little longer than I had hoped, but hey, other plans have had worse! The idea is that we take these three items to the graveyard, use the bridge to get the elevator key, and then we finally have our key, rug, and rope we need to complete Zaks' castle, if after a bit of unavoidable item cycling. So you see where including the rug can mess up the plan a little, but it's still not bad, right?
I watched Ununoctium's speedrun again today, only to find that it followed a completely different route than I had dreamed up. Two minecart trips? Really? Well, maybe working on this TAS route will also be beneficial for someone looking for a new unassisted run route. I am starting to think the Genesis version may make for the nicest run after all, just because you can get through it so quickly. Please speak up if you have any new ideas or can fix any flaws in my ideas, maybe help me flesh out the treehouse routes a little better.
It had always been called as such, with a description like "It's frozen solid," but I like how they went to the effort of putting in an alternate graphic.
The Genesis version is pretty cool actually, with the most advanced graphics and the most sound effects and not as many omissions as the Amiga version. The Amiga version is interesting too though, being largely similar to the Genesis one but sharing some traits with the IBM-PC version like tweaking the difficulty with only 3 password checkpoints in the entire game and requiring 15 candies to gain an extra life rather than 10. I think Cosmic also runs faster on Amiga, the way he does in the PAL NES version, except he doesn't jump higher like in most other versions. The Genesis version seems to have neither the higher jump nor the faster run, although it's still pretty easy with being able to change direction mid-air.
Oh, so, a new TAS? I don't think I'll be making one, but if someone feels braver about messing with luck manipulation and car acceleration in the last half of the game, I would like to see that improvement! Right now I'm just writing more notes in case anyone ever needs an article about Cosmic Spacehead and its development...
Some more updates: I played the NES version some more this weekend, and I found a few more glitches. I discovered that Linus can use the blowpipe before he's picked it up, and even if he can't reach it! Just stand underneath and hit Use on it, and Linus will pull out a second blowpipe and blow. Of course the game isn't fooled enough to actually put the blowpipe into your inventory after this, so it's probably useless. I think there just isn't any checking done whether those platforming tools are in Linus's reach when Use is used, but they don't go anywhere if they didn't come out of the inventory. Interestingly, all the platforming tools can't be Used on other objects in the hub; the Use command immediately gives a failure message instead.
Also I found more weird entrances. In the camera shop, if you move Linus to the edge of the room and choose Use Door, then he will hit the edge of the doorway and fade out the area immediately instead of running all the way to wherever you clicked. I don't think that's useful at all because Linus is already in front of the door. But I found something better at Cape Carnival: Run all the way to the T-shaped post that triggers the "Hey, bud..." message, then choose Use Secret Tunnel. Linus will immediately enter the tunnel after a single step! I don't know yet if this saves time, since Linus has to run almost as far from the attendant after the race as he would to the tunnel, but it's definitely worth checking. There's more: You can exit the post office immediately from the left edge of the screen! You could also do this with the barriers at the border, but you don't really have any reason to. Oh, and none of these places work in Cosmic Spacehead. So this was the glitch that Cosmic Spacehead fixed that was causing the different behavior at the Formica City wall.
Then when I got to the space station, I started playing around with leaning against walls before picking up items, and Linus would pick up the item before reaching it, and once I got Linus to pull out a blowpipe while running over the blowpipe, but nothing too special. But then, in sector No. 3, I realized something simple: After crossing my bridge, I could just pick it up right away, because I could reach it from the other side, and I didn't need to cross the bridge again in that room. Sheesh, why didn't anybody remind me that I didn't have to go back for that bridge? Linus Spacehead fans are slacking! I don't care how cool you thought that glitch was, there was NO REASON for me to be such a dummy about that! Maybe there'll be a new TAS after all...
As I write this post I'm testing out the frame-by-frame movement basics. Something I noticed while positioning Dizzy is that pushing Left for just one frame from a standstill will cause Dizzy to move a total of 4 pixels to the left, but pushing Right for just one frame will cause him to move only 3 pixels to the right. So alternating taps of both directions with time in between for Dizzy to stop will cause him to travel a net distance of 1 pixel to the left. I think what's going on is that Dizzy must move for 3 frames in a row, and starting a leftward walk from a standstill has a different start-up pattern: 1, 2, 1, 1, 2, 1, then 2 pixels every frame until you stop again, whereas if you push Right from a standstill, the start-up pattern is 1, 1, 1, 1, 2, 1, then all 2s. If you press Left while already walking to the right, the start-up pattern becomes 1, 1, 1, 2, 1, then all 2s, or that last pattern minus the first 1, I think.
What "Dizzy must move for 3 frames" really seems to mean is that once Dizzy starts walking, the game will only detect D-pad input--or the lack thereof--on every 3rd frame until Dizzy stops moving again. So you could tap the direction button at 20 Hz, and it would have the same effect as holding it continuously. The game also only accepts the C (jump) button on those same 3rd frames, but accepts the B (grab) button 2 frames after those frames--that is, the frame before the one on which you could control Dizzy's next move.
Then the ingredients will pop in immediately, without Dizzy having to toss them first, and the full bottle will pop into Dizzy's inventory instantly too! I suppose this has a similar basis to that "MegaMan 4 power absorption" trick, where the game wants to arc the objects over to some center location, but gets confused and skips something when the objects are already centered. I started thinking about where else this idea could be used to skip a throwing animation, but most of the times Dizzy throws something it's to a character who would knock him back before he could get centered inside them, except...
The shopkeeper! Yeahhh, immediate bean!
One thing to consider with these tricks is that they may require "subpixel" placement to work--well, since Dizzy moves at 2 pixels per frame most of the time, it's probably just pixel placement. See, there appears to be an element of luck involved in certain maneuvers, like when Dizzy walks off a step, he may or may not grab the star hanging in front of him, and when Dizzy steps off onto an elevator-width gap, he may fall through or he may step across to the other side, so I'm guessing it has to do with whether Dizzy was standing on "even" or "odd" pixels beforehand. Occasionally you could use a wall-bump to switch Dizzy from odd frames to even frames, but with frame advance you can see there's the briefest period of acceleration where Dizzy only gains 1 pixel per frame, so I think some kind of start-and-stop trick would probably be the best way to fix your position. Yeah, this'll take some more study, figuring out how Dizzy's speed works and the minimum number pixels he will travel with one step.