Amillusion/guide

Brambles
(The Radioactive Effect is required.)

Go south and interact with the mouth. Equip the Radioactive Effect to illuminate the area. Head northwest past the purple NPC and interact with the skull covered in thorny vines.

Star
Go right and enter through the double doors. Head northeast and interact with the star.

Radioactive
Go down and left and enter the closet. In one of the rooms on the right containing a door NPC is an exit out of the building. Head down the stairs and make your way through the maze to an opening to a green pool of radioactive liquid. Walk around in it for a little while to get the effect.

Cosplay
Go left and interact with the green orb. Head north and west and enter the yellow and orange archway. Find and interact with the thin upright doll body.

Mad
Go down and right and interact with the sign. Find the ostrich head sticking out of the ground. Interacting with it will take you to a teleport maze. Choose the bottom head on the first platform and carry on until you hit a yellow island. Follow the path to the end and interact with the ostrich head.

Honey
Go up and interact with the purple flower. Head north through the gap in the top of the area. Find and interact with the picnic spread.

Bad Girl
(The Radioactive Effect is required.)

Go down and interact with the mouth. Equip the Radioactive Effect to illuminate the area. Head northwest and interact with the purple NPC. Carry on east until you hit a yellow arc, then go south and interact with the bobbing red object. Next, head southeast and between two green pillars. Directly northwest are a cluster of circular objects, interact with the one with face on it.

Green Mouse (Souris Verte)
(The Star Effect is required. There are two parts to obtaining this effect.)

Go up and to the left and enter the spire. Locate and step on the pink puddle and you'll be transported to Soup World. Find the yellow phone and enter it. In the next area, equip the Star Effect and use it to chase down the green mouse running across the area. Interact with it to catch it.

Once you have the mouse in your inventory, equip it press Shift to dunk it in the yellow liquid covering the area. Bring the mouse to cauldron near the trio of gentlemen. Interact with it to exchange the mouse for a Key, the true effect.

Cougar
Go up and to the right and interact with the water droplet. Navigate your way through the baths to an entrance in the side of one of the structures. Go left and follow the path. Get on the boat. Keep making stops throughout the "life journey" by remaining in the room with the angel captain until the boat comes to a halt. Visit each stop and repeat this process until you arrive at the fifth stage of old age. Interact with the radio near the tombstones.

Screw
Go up and to the right and interact with the water droplet. Navigate your way through the baths to an entrance in the side of one of the structures. Go left and follow the path. Get on the boat. Keep making stops throughout the "life journey" by remaining in the room with the angel captain until the boat comes to a halt. Visit each stop and repeat this process. At the sixth stop you'll end up in the Clock Room. Climb the ladders to reach the entrance to the Silhouette Rooms. Make your way to a dead end with a white structure in the room's center. Interact with it to make it light up and obtain the effect.

Gossip
(The Star Effect and Radioactive Effect are required.)

Go down and right and interact with the sign. Find the ostrich head sticking out of the ground. Interacting with it will take you to a teleport maze. Choose the bottom head on the first platform and carry on until you hit a yellow island. Once there, choose the other head. From the next island, navigate your way to a dead end with a blue ostrich head. Continue on from where you're warped to while avoiding the chasers and pass between two blue squiggles.

In the next area, step (physically, without hovering while using the Star Effect) on tiles with shapes until you're transported to an area full of them. Equip the Star Effect and look around until you locate an "X" square to the left of a door on an isolated platform. Unequip the effect only once you are on a square adjacent to that particular "X". Stepping on it will teleport in front of the door.

Once inside the hospital, carry on right to the end of the hall and take the stairs up to the third floor. Equip the Radioactive Effect in front of the third door from the left to pass through the radioactive zone. Through the door at the end is the Labyrinth.

This area is VERY difficult to traverse safely: there are speedy worm-like chasers that will teleport you to inescapable rooms throughout, as well as demons running in a linear manner that will force you awake if you collide with them. Navigate your way to a dead-end chamber with a statue in the center. Interact with it to remove its head and obtain the effect.

Normal
You start the game with this theme.

Sunflower
Go down and left and enter the closet. In one of the rooms is a sunflower NPC, interact with them to get the theme.

EPACSE
Go down and interact with the mouth. Equip the Radioactive Effect to illuminate the area. Head northwest and interact with the purple NPC. Carry on east until you hit a yellow arc, then go south and interact with the bobbing red object. Next, head southeast and between two green pillars. Pass through the thorny archway and interact with the bus stop until a bus arrives. Wait on the bus until it comes to a halt. Exit through the square building to EPACSE. Find and interact with a sign on one of the cubes to get the theme.