In Yume Nikki, there are three vending machines, found in the Dense Woods A, Hell, and the Docks A, from which the player can buy 'health drinks' to increase Madotsuki's health.
Yen
Yen is the currency system of Yume Nikki and is required to operate the vending machines. Other than that, it has no other function in the game.
Yen is acquired by killing NPCs with the Knife effect. Most killable NPCs have a 1 in 8 chance of yielding 100 yen when killed, though there are some exceptions to this:
- Organoid, who can be found in the Sky Garden, always produces 100 yen every time they are killed. This is possibly due to the fact that they teleport away when Madotsuki gets close, making them difficult to kill.
- The Goblins in the castle room of the FC House have different chances of dropping yen. The small Goblins have a 25% chance of dropping 100 yen while the big Goblin has a 50% chance of dropping 200 yen.
There is also a room in Number World filled with Wheelies known as the Stabbing Room by fans due to the method of clearing it with the Knife effect. It can yield a moderate amount of yen when the room is cleared, as the 1/8 chance of dropping yen is still the same for the Wheelies.
The amount of yen in your possession can be checked in the pause menu in the bottom-left corner of the screen. The fact that yen is acquired while dreaming, but stays in your menu after "waking up" has led to the theory that Madotsuki is always dreaming, but this could just be a remnant from the game's engine.
Health
Vending machines sell pink drinks that increase Madotsuki's health points, represented by hearts in the pause menu. However, there is no practical benefit from this as there are no damage hazards that can physically hurt Madotsuki in her dreams. Therefore, there is no need at any point in the game to increase Madotsuki's HP other than for personal satisfaction of the player, or as a mark on the save data window. The reason for its inclusion is that Yume Nikki was made in RPG Maker 2003, a game engine typically used for RPG games that utilize character health points in battles. It is also possible that the process of removing health points from the game was simply too difficult.
Vending Machines
Below are details about the three vending machines found throughout the game.
Dense Woods A
This machine can be found in the first Dense Woods section and can be immediately seen if the player enters the Dense Woods from Puddle World. Here, it dispenses a small can of 'health drink'. It costs 100 yen and increases Madotsuki's HP and max HP by 1 point.
Hell
This machine can be found in Hell and can be found near the Nenrikido found in the Footprint Path. Here, it dispenses a medium bottle of 'health drink'. It costs 130 yen and increases Madotsuki's HP and max HP by 1 point, and has a 33% chance of increasing both by an additional 1 point.
The Docks A
This machine can be found in the Docks and can be immediately seen if the player travels through the tunnel in the Sewers that requires the Midget effect. Here, it dispenses a large bottle of 'health drink'. It costs 150 yen and increases Madotsuki's HP and max HP by 1 point, and has a 50% chance of increasing both by an additional 1 point.
Gallery
A vending machine in the manga.