There are 24 effects that the player can find, each of which affects Madotsuki's appearance and often abilities. Very few players achieve the goal of gathering all effects alone, and walkthroughs exist mainly to help find each one.
Effects
Bicycle
Madotsuki rides a bicycle. It dramatically increases speed. Madotsuki cannot get into beds when this effect is on. Pressing '1' makes the bicycle's bell ring.
Frog
Madotsuki's head becomes that of a frog. Using this effect makes Madotsuki move faster in water. Pressing '1' makes her hop once.
Instructions
The only effect you start with. They briefly explain how to play the game.
Knife
Madotsuki holds a kitchen knife in her hand. Using this effect results in her stabbing whatever is in front of her. Pressing '1' makes her change the hand she is holding the knife with.
Severed Head
Madotsuki loses her body. She can still crawl around with just her head, but this reduces her speed to almost nothing. It is the slowest effect in the game.
Witch
Madotsuki dresses up like a witch. Can be used in the department store.
Pseudo-effects
Chair
By sitting at Madotsuki's desk in the dreamworld and pressing 'Z', Madotsuki can pull the chair away and start to hop around on it. This is very slow and grants no extra abilities, although it does change her appearance.