MKCocoon's 38:20, current Any% WR: https://www.youtube.com/watch?v=4vCqkYQhYqI

Beginning of the run- RNG manip for perfect Waddle Doo movement, slide on the Waddle Dee in the middle slightly faster than puffing up to get both Waddle Doos. 14 powers until Wheel. 4 frame window to get Wheel
0:21- If you run immediately while getting out of Wheel, it cancels the animation of Kirby skidding on his butt, which saves a bit of time. We do this through every door in the game we go through with Wheel, and whenever we need to run a little bit after Wheel in general. This time definitely adds up!
0:35- Cloud minigames happen at the end of every level. You need to press A and/or B to stop the cannon. You're aiming for a 7 here, which is a 3 frame window, but you want the lowest 7 you can possibly get. Getting a low 7 is frame perfect, but saves the most amount of time. Mid 7 and high 7 are alright too. If you get between a 7 and a 6, you waste 1 1/2 seconds grabbing the cloud so that's what you always want to avoid. This is something you'd get the hang of by doing more runs
0:59- We get rid of Wheel, suck up 2 Bronto Burts, kill the Poppy Bros., then get Wheel back all at once.
2:17- Faster Mr. Frosty pattern saves a small amount of time, but obviously luck
3:01- Frame perfect hits save a small amount of time on Whispy Woods. If you press up right before getting the star rod, you won't bonk on the ground and save a little bit of time
4:22- We need any power at this point so we can turn around and get an easy double star. That allows us to destroy that Wheelie boss in 1 hit again, netting us a Wheel power
4:38- Floating here skips the rest of the room
5:07- This water room loses a lot of time for many runners. That boost Cocoon does to take out both fish is tricky. You have to time your B press at the right time so you don't move down while spitting out water. Saves a small amount of time and makes it easier to get past the other fish in the room.
5:20- Cocoon moves in a way here to manipulate the Bronto Burt so he can take it out while also avoiding the Waddle Dee there and moving fast enough to avoid the Cappy hitting him, making it so he can keep his Wheel
5:26- First arena of the game, where you have to take out all the enemies to advance. Cocoon does 2-3 Wheel, where you keep Wheel through this arena to save time on movement in the next 2 levels. Saves like 7-10 seconds I think. He gets rid of Wheel at a precise spot so it bounces around the room while he takes out 6 enemies, all while avoiding accidentally destroying his power, then gets it back in the top right corner, only to get rid of it right after so it bounces around the room while taking out the remaining 5 enemies, sucking up the last one along with his power at the same time. This is probably the hardest trick in the game. I personally didn't do it in my former WR time of 38:23, but if I went for WR again, I'd grind this strat in order to more easily get a PB.
6:11- Boss manipulation! Cocoon moves to certain sides of Tick Tock there so he does different things. In this case he runs to the right of him so he runs into the wall, allowing him to take him out easily. He has to get out of Wheel before he hits the wall every time so he doesn't bonk there, which wastes time and makes it easy for him to get hit and lose Wheel
6:23- Wheel saves the most time in this room
6:59- This room is where you'd normally get Wheel, so the timesave from 2-3 Wheel is done. Not having to get Wheel in that room also saves time!
7:17- First room we get Hi Jump in! In this game, we can cancel Hi Jump by pressing B, which that cancel also has a hitbox that does a bit of damage. This allows for a lot of cool movement options and boss kills in the future, such as the boss coming up very soon!
7:41- Paint Roller can go to either the top right, bottom right, or bottom left corners of the room at the start of the fight. Top right is fastest, bottom right is slightly slower, and bottom left wastes about 2 seconds. For the fight, you want to do 5 Hi Jumps + cancels next to Paint Roller so you quick kill him. You need to be RIGHT next to him though in order to do the most damage. If you're too far away, it won't do as much as it could. For this run, Cocoon gets the bottom right pattern and he waits for Paint Roller to start painting something before hurting him, which wastes a second but guarantees a 5 hit. Idk if that's worth it, but I don't think it's a bad option either
8:12- For this Tick Tock fight, Cocoon reacted to the usual pattern you'd get from Tick Tock, but he actually got the fastest pattern in this case, which saves a little bit of time on movement. Probably wasted a second here just doing that compared to an optimal fight
8:43- Cocoon goes for a safer strat where he cancels Hi Jump and holds up, allowing him to get through that 1 tile gap seamlessly. You can also Hi Jump through that gap to save a bit more time, but it's harder to do consistently.
8:50- This Waddle Doo on the stairs has a random pattern. If he stands still and attacks, you have a small frame window to Hi Jump him to get past. Cocoon got the moving/jumping pattern, which is the best one though
9:00- Normally you'd drop Hi Jump in this room and get Sword, but Cocoon opts for keeping Hi Jump instead, which saves a little bit of time in the level and in 3-3, but makes the Bugzzy fight harder.
9:12- Keeping Hi Jump skips waiting for those two penguins to stop blowing ice
9:14- This fight is super tricky and luck based too. What Bugzzy does is 100% random, and if he grabs you during the fight, it can waste up to 6 seconds depending on which attack he does. With Sword it takes 7 hits, but with close Hi Jumps, like what Cocoon does here, it takes 5 hits. Cocoon got a great pattern and was able to get past him easily.
9:47- You'd normally get Hi Jump back here, but with the WR strats Cocoon uses, he keeps it and saves a few seconds not having to get it
10:27- 2nd arena of the game. Here the idea is we keep Hi Jump through it so we can use that for the rest of the world after it until the end. We Hi Jump every enemy, starting from the right and going around the room to the left, then taking out the finally enemy on top. The 5th, 6th, and 7th enemies are random how they move, but the 5th and 6th ones are the ones you'd need to worry most about. The purple spear enemy bounces around erratically and you need to react to where he goes. The 6th one will be either near the wall or near the edge of the platform so reacting to that is important too. Cocoon got hit by both these enemies unfortunately, but sometimes that just happens. He's told me himself that he's not that good at that arena and 3-4 is one of his most hated levels. This is a big place someone can capitalize and save time on him if someone were to contest his WR.
10:46- Be careful not to hit an enemy out of this room, or else you won't be able to cancel Hi Jump when you get in front of the door. If you hit an enemy as you're canceling a power, you won't be able to cancel that power, whether it's Hi Jump or Wheel.
11:07- We move so fast through this level that we're able to keep this candy through the whole thing, which means we just spam B on Bonkers once we get to him for an easy kill
11:22- Fast strat through this room is a bit tricky, but looks cool and saves probably a second. Puff the top block, slide, then spam Hi Jump until you're past the blocks. Shoutouts to Marche_ for finding that one. Otherwise we slide through the blocks then Hi Jump twice.
11:37- If you don't move perfectly in this room, you can't take out that Crash Bomb before he hits the floor, which this saves 2 seconds if done correctly. You need to run immediately and jump at the right time in order to get in a position to hit that Crash Bomb before he blows up. If you get hit by him, you're sent into a big tumble animation that wastes a few seconds, so be careful!
11:50- The frog is random what he does, so you need to react in case he moves in your way. Thankfully this went fine for Cocoon.
12:32- Mr. Shine and Mr. Bright are a 50/50 chance as to which one you can hurt first. Cocoon opts for the middle strategy of not standing near either one of them, but if you'd guess correctly normally, you'd save about half a second over what he does, and it's also more fun! All you need to do for the fight is stand near them and spam B. They take 3 Hi Jumps + cancels to die
13:22- If the Tornado enemy starts attacking, you can't go for a mix off him and the Blade Knight for Wheel. Wheel can save about 5 seconds in 4-2 if you get it, but unfortunately it is luck to get this time save. He went for a backup mix off the Sir Kibble and Waddle Doo at the end of the room and unfortunately failed that. Wheel is the 5th power in that mix in this case
14:20- You get Spark for the double Poppy Bros. fight. They can either both jump up, right one jump up left one jump back and forth, left one jump up and right one jump back and forth, or they both jump back and forth. You want them both to go back and forth or right jump up and left back and forth ideally because you'll be in a closer position to the door that spawns.
14:46- Most runners opt for the top path on this level, running on the zeppelins instead, but Cocoon opts to go for the middle path here, which is slightly faster if done correctly
15:02- If you get Hi Jump here, it saves 2 seconds if you keep it until the end of the room. Cocoon is able to do this for a free time save!
15:32- 4-4 Wheel is a trick that's usually the bane of most people's existences. It's a 14 power mix for Wheel that saves about 7 seconds in the next 3 rooms. Failing it is pretty brutal especially being this far into the run. The Ball enemy as well moves randomly, so when you go to the right then respawn him, you have to react to how he moves, which can be very tricky
16:07- We keep Spark after the Phan Phan fight now. Until a few months ago we got Throw from Phan Phan and used it for the rest of the level and for the arena in 4-5, but keeping Spark is faster now for the last room by about 2 seconds with good movement!
16:53- Powerless 4-5 Arena saves a few seconds over the old Throw strat. Start on the left, go to the middle, back to the left, and then over to the right all while spitting enemies at each other. If done correctly, you can suck up the last 2 enemies at the same time then suck up the last enemy while going into the door
17:40- The 2 frogs in your way in the water are random where they go, and spitting water at them is slow, so being able to react to where they go can save a lot of time. Cocoon elects to play it safe and takes out the 2nd frog in order to get past him without losing time.
17:52- This Tick Tock fight is random what he does, but Cocoon got the pattern that you want in the fight. Sometimes he'll run and slide into you, which is very hard to react to without getting hit. He can also sometimes just jump like 5 times in a row then try to run at you, which makes the fight free and it's the fastest pattern!
18:15- Cocoon gets Hi Jump here instead of during the world 4 boss fight. This saves about a second
18:31- Kracko is unique in that he has the only fight in the game with a level before it. Timing your Hi Jumps so it takes less time to get on top of the next cloud saves the most time and adds up, along with avoiding killing any of the Starmen along the way.
18:47- Cocoon elects to go for a risky quick kill strat. Instead of 5 hits + cancel hits, you do 6 hits to take out Kracko, but you move right next to the lightning hitbox the whole time, which is HUGE. Doing so saves a few seconds. You also want to be as close as possible to the middle of the screen when you beat Kracko to save time on Kirby walking to the center
19:17- This bottom path is faster than the top path. It's faster to get to that door and using the Stone in that door allows you to fall faster than normal
20:06- This is the first time in the run we get Ball, which is the most powerful ability in the run. 2 rooms from then, Cocoon goes for a Ball movement strat that saves a small amount of time and negates having to react to the Blade Knight pattern in that room. He unfortunately messes up the 2nd part of it going into the door though. 2 rooms from then he uses Ball in that small corner to avoid dealing with enemy luck going up that room. He also uses Ball to fall quicker than normal towards the door exiting the room.
20:29- Cocoon rolls into Bonkers here in order to hurt him, then bounces off the wall to get the 2nd hit. Yes Ball 2 hits minibosses.
20:36- Using Ball here saves a little bit of time on movement
20:51- Using Hi Jump and avoiding all the enemies is the fastest movement in this part of the level, faster than jumping and using Hi Jump
21:22- Wheel Jumping on these blocks is faster and safer than running over them normally.
21:30- Turning around with Wheel and immediately getting out of it after the turn allows you to get a lot of momentum in one direction. The community calls this a "Shasturn", named after yours truly. It makes the spike room a lot faster and I'd even argue easier. Cocoon gets all 3 possible in that room here, the last one being the hardest to get.
21:58- If you use Burning at the right spot, you can use 3 in a row over that long platform, saving a few seconds over the safer 2 Burning strat or going around.
22:04- This arena is a bit trickier to follow than the others. You swallow the enemy on the middle left without going on that platform, then spit it at the enemy across the way in between his attacks, suck up both the right-most enemies to get a double star, then spit it across the middle row to take out 2 enemies (one being offscreen just spawning in), spit the 2 enemies on the bottom row at each other, then go to the top and time your spit correctly so you take out both the remaining enemies at once. It's only a few frames to get that last timing, but it saves a few seconds so it's worth it
22:22- This Ball strat saves 2 seconds if done correctly, but it's pretty precise and if you mis-position yourself, you just die.
22:30- Sliding into this corner, using Ball, then holding right allows you to get the Tomato in that room for a full heal and avoid all damage from the randomly moving Sparky enemies, PLUS it saves 1 second!
22:56- Cocoon uses Ball to get through that Shotzo's projectiles without getting hit. Most runners will elect to just jump between the shots, but Cocoon's way is definitely safer.
23:18- The Ball setup Cocoon goes for here saves a bit of time over regular movement and the speed he gets from Ball gets him right in front of Fire Lion so he can just jump and Ball to 2 hit kill him easily! You need to make sure not to destroy his body though because you need Burning for the next few rooms