Yooka Laylee and the Impossible Lair is a light and fun game with exciting levels that manifest right from the start. One of its most interesting features is the addition of state changes, elements with which you can interact in the planetary world to influence the game of previous levels, completely changing the approach of the players.
Each of the game's chapters has a variation, although unlocking them can be somewhat unintuitive. This is where this guide comes in.
Chapter 1: Capital Causeway - Chaos: Much later in the game you will come to a lighthouse; talk to the fisherman nearby, then return to the area near chapter 1. Setting up the yellow tents near the water's edge will allow you to talk to the fisherman, thus unlocking the change of state (remember to take the tick ... Tock tonic while you're here!).
Chapter 2: Factory Cold - Flooded: This one is a bit more involved. From the entrance to Chapter 3, head north, take a right, then head south. A bush of water berries is there; use it to rehydrate all the plants in the north, then use the rehydrated water bay to rehydrate the plants on the left. Use the bouncing flowers to continue to the left (be sure to grab another bay of water and move quickly) and rehydrate one final flower. Bounce up, head all the way south and hook the last one on the left. You will find a Pagie that will task you with completing a Space Invaders-style challenge level, after which Flooded will be unlocked.
Chapter 3: Wild Web Woods - Wilder: Remember where you first grabbed the water bay for the above? There is a berry bomb bush near there (to the right and north, after entering Chapter 5) that you can rehydrate. Grab the bomb, run fast and throw it at the destructible block near the water berry bush. Grab the block at the end of the cave, bring it back to the switch near the entrance and go up. We, the nearby bomb hunter, drop the switch on the ground, then flip it! It's less complicated than it sounds.
Chapter 4: Frenzied Fountains - Frozen: Unlocked immediately after the completion of Chapter 4 by your kind Queen Phoebee.
Chapter 5: Panting Glade - Cultivated: Directly north of the Bomb Bush used to unlock the Wilder State Change from Chapter 3, there is a cage with a key; pay 1000 quills to open the cage and bring it to the locked door southeast of you. There is a series of simple puzzles inside, after which a bomb bush appears. Use the bomb to smash Rampo's teeth and the water flowing outside (you may need to flip a switch if you haven't already), amplifying Chapter 5!
Chapter 6: Evaded Saw Blade - Stuck: Collect the honey for the Grumpy Jar directly north of the Chapter 6 entrance (located through a series of unlocked doors taking a circular path to the right after burning the bramble in the forest and Buddy smashing the tree on which you end up). She will tear up chapter 6 for you.
Chapter 7: Production Path - Panic: Available immediately after playing Chapter 7 normally (you are dropped off at the entrance of this state change).
Chapter 8: Windmill Way - Windy: You unlock this area after repairing Fannee's fan by spending 1 feathers to unlock its missing parts in the adjacent area. The first is fairly easy, but the second requires you to follow the wind of other fans at the top of the map, going left into the adjacent forest area (like you did for Chapter 000). Go straight south after entering, move the massive block along the predetermined path (it can't stray too far from wind paths), and set it on the switch. The second room is directly northeast of you.
Chapitre 9: Urban Uprise – Updraft: Unlock the critical point near the underground entrance to the desert area. Use it on the locked door and place the hose in its appropriate receptacle. Go back outside and rearrange other pieces of pipe that are now out of place and voila! More wind.
Chapter 10: Ropeburn Bridge - Reoriented: Proceed as you would for the Change of State unlock in Chapter 9, but after placing the pieces where they are, use the water bay to put out the fire nearby. Go through the chimney and the relatively linear area until you reach the swivel platforms. Hit the switch, and you can now enter Rerouted when swinging.
Chapter 11: Conveyor Chaos - Crosswire: Complete the Pagie challenge in this region; this will open a red staircase. Take it down, flip the pool switch and enter the underground area that it reveals. Complete the series of simple puzzles using mechanics you've seen before (fire berries to destroy brambles, water to rehydrate other plants, bouncing off flowers), and you will get a switch; slam it for your reward.
Chapter 12: Buzzsaw Falls - Frosts: Unlocked as soon as you get here, slide across the frozen lake to the book.
Chapter 13: Quest For The Cliff - Cold: Rehydrate the flower next to Nimbo, then heat it with a scorching berry to thaw the lake. Push the block / crate nearby, so that it prevents you from slipping when entering the chapter. Refreeze the lake, and enjoy!
Chapter 14: Hanger Hazard - Hung: You have to complete two Pagie challenges for this one; the first north of the area under trees that form an arch. Toggle the switches of the newly unlocked area to an easy-to-clean wall. Then use the falling key to open the cage on the ledge below with another Pagie inside. Complete their challenge and flip the newly accessible switch, cross the bridge and hit another switch. That's it.
Chapter 15: Turbine Problems - Tide: Near the level entrance is a bramble; Use a burning berry to destroy it, then use the bomb berry bush trapped inside to destroy the destructible blocks located nearby. Let go of the bridge, take another bomb and destroy the nearby sandcastle (near the two caddies).
Chapter 16: Queasy Quay - Climb: Bomb the stone blocks under the nearby bridge (in the river bed) as above; push the switch in and turn it on. It's pie.
Chapter 17: Boom Blossoming Explosion - Breakthrough: Enter the lighthouse (near where you spoke to the fisherman) from behind and flip the switch. Go back to the main door, go through the docks and get to the top. Push the cart down to activate the scene change. This one is a bit of a pain as you have to come here every time you want to.
Chapter 18: Pumping powered by plants: Go to the far right of this area and collect the crate by bringing it back to the talking crate. Enter through the door, navigate the platform to access the door and solve a simple puzzle in the new area. This one takes longer than difficult.
Chapitre 19: Shootout Scareship – Smoggy: Completing the Pagie challenge in this area will drop some ledges. Climb them up and use the crate to make your way through the wind tunnels. Go north until you reach a new room with a container. Move it on the grid, then use the switch to drop it below; it will be futz with the furnace, opening the change of state.
Chapter 20: Scroll of Scareship - Docked: This one is a bit involved. Jump on the cart at the far left of the underworld area, hopping on the book, then some flowers to reach a new area. Inside are switches, which will drop a crate, similar to the ones above. Just like unlocking Chapter 19's state change, you need to drop a crate on the ground. Unlike that, you'll have to do this a few times, ending up dropping it in a cart and shining the lights along the way. Once all three lights are on and the crate has descended to the bottom, place it in front of the moving cart to stop its progress and access the final state change.
Hope this makes your trip to the Impossible Lair a bit easier!