Motorcycle
Can be found in Garden World from the hub then go down a little bit and to the left. Similar to Madotsuki's bicycle, allows you to move twice as fast, you will be using this A LOT in your adventures.
Boy
Can be found in Geometry World from the hub.
Chainsaw
Can be found in Grave World from the hub. Go up till you see the spade and then to the right until you see a giant heart vomiting. Go through the hole and you will notice the map change and the music will soften. From here go to the left and look for a door on the wall to enter The Hospital. Now continue going left to reach a door. Go through this and keep going until you reach the very end of the corridor. In this room there will be three doors go in the far right one and go through the left door twice. From here follow the path until it turns North, instead go south and you should see a red spot on your left. Ride over it and you will be teleported to a new area. In here go through the green club looking things and you'll run into the chainsaw sooner or later. Similar to Madotsuki's knife, this can be used to kill enemies/destroy objects and walls, another very useful effect.
Lantern
Can be found in Forest World from the hub. Go left and AS SOON as you see the bench go straight down. You'll see a hole in the ground, go around the cones and fall in. From here go down, right, up, right, immediate down, second right, up, right, the lantern will be on the far wall. Similar to Madotsuki's Lamp, this can be used to light up dark areas and has a few other special uses too. Also catches some characters on fire.
Fairy
Note: Dangerous Route! Use Motorcycle
Can be found in Gravel Maze World from the hub. Go straight right then up as soon as you exit the path and keep going until you see a taxi and press z in front of the passengers seat to reach The Highway. From here just keep going right until you reach a forested area, it will take awhile. Now go down then right to see a dark robot, you must pass directly in front of him or he will block the way then just go right into the trees to go to the next area. Here just talk to the fairy to get the effect. This can be used to get into small areas and Urotsuki does a spin if you press z. Also can be sometimes used to pass over small gaps.
Spacesuit
Can be found in Marijuana Goddess World. Go straight up until you see the grey blob things then go left until you see a giant pink door. Go in and go down into the next room. Go right and go up the stairs. Keep going right then go down the stairs and to the left into the next room. Continue going left until you reach a ladder, go up it to enter Japan Town. Keep going left until you see a red mailbox. Press z in front of it to go to the Museum. Go right, down, then down again to enter the Factory. go in the middle door then go down then right past the first door and into the second door, go in there. Now go in the right again and you should see the spacesuit below you. This can be used to float across gaps and is required to move around in some areas like space. (durrhurr)
Glasses
Found in the museum. They can be used to see things not visible without them.
Rainbow
Floating somewhere in the Puppet show world (The door with the moon and stars.) Can be used to find secret passages and in some cases make a rainbow.
Wolf
Go to Marijuana Goddess World and go down until you see a blue neon thing. Go enter the blue neon thing on the far-far left. Go up, right, then top path until you see a candle (?). Go diagonally until you see a blue candle. You are now in a warp maze. Go right up right right right up. Go left and talk to the person. The wolf effect either repels or attracts certain NPCs.
Note: Equip wolf while in bike to ride around as a wolf on you bike.
Medabomb
Like the Medamaude from Yume Nikki, it sends you back to the main hub.
Telephone
Go to Marijuana Goddess World and go right until you see that lightning thing. Go up and enter a dark room. Keep on going down until you enter a room that has a little girl and interact with the telephone. Hold Z to make it ring and can be used for various things.
Maiko
Found somewhere in the shrine area. When you hold Z, she bows.
Penguin
Go play the game in your dream and the effect gos into your inventory.
Bug
Note: Dangerous Route! Use Motorcycle.
Go to Marijuana Goddess World and go down until you see a blue neon thing. Go enter the blue neon thing on the far-far left. Go up, right, down, left, down, right, and up. Chainsaw the bug thing up on the edge. Be careful not to get caught! Then go up and touch the pedestal and get the bug effect. The bug effect is known to attract things.
Note: It's risky to use invisibility because the enemy goes extremely fast and might bump into you.
Spring
Invisible
Can be found in space. To get there, you must first go to Marijuana Goddess World and go down until you see a neon... thing. Enter that and go to the other one on the left. Go to the cone-head on your right. Go straight ahead and up until you see a dead end. Then turn to your right. Go straight down after that and you will be teleported to a bowling alley. Avoid the bowling balls and go into the bowling pins. Go down and turn right when you see a yellow bowling ball. When you see a blue bowling ball, go down and turn right when you see a pink bowling pin. Go into the dots surrounded with bowling pins. Go straight ahead in the bowling alley and you'll be teleported into a dark maze. Use the Rainbow Effect to make the paths visible. Go to the Lollipop Tree and kill the girl. The maze will be visible when you return from the Lollipop Tree. Go back to the entrance of the maze and you will be teleported to a place with a man in an okami mask. Just go in whatever directions he's facing and you'll be teleported into space. Go straight and follow the spiral to get to the Invisible Effect. It can be used to hide from enemies.
Cripple
Go to the Japan Town and go up the dark alley. Keep on going right until you enter a nonsensical area. Keep on going up until you see a boy who seems to be hurt. Interact with him to get cripple effect. It is simply cosmetic.
Tall
Can be found through a painting in The Museum. There are two ways to get here. The first is to follow the route to the Telephone Effect. The second is to go to the blue neon place and go to the one down the map. From there, you will go to your left until you see an easel. Enter that. When you're in the Museum, you to the second floor and enter the second last painting to the right. Use the Glasses Effect and interact with the blob until the background turns black and white. Down the map, you will see a beet. Enter that and you will ne teleported to a maze. Go to the blue man on top of the maze. Next, go down and to the farthest right to pass through the trail of blood. Go up the path beside the Talking Tree and you will be teleported to a laggy map. Find an orange-red diamond on your right and enter that. You will see a pink body in a pool of blood beside a sign. Interact with it and you will get the Tall Effect.
Cactus
Cake
Go to Puppet Show World and find a arch-way. Wander around until you find a silver fork. Interact with it and keep on going left. When on top up the fork, talk to the girl. The cake effect drips when you hold Z. Simply cosmetic.
Child