In Yume Nikki, there are three vending machines, found in Dense Woods A, Hell, and Docks A, from which the player can use yen to buy 'health drinks' that increase Madotsuki's health.
Yen
Yen is the currency system of Yume Nikki and is required to operate the vending machines. 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 a couple exceptions to this:
- Organoid, who can be found in the Sky Garden, always produces 100 yen every time they are killed. This is likely because 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. Killing them is the fastest way to gain 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 bottom left of the menu. The fact that the yen acquired while dreaming stays in your menu after "waking up" has led to the theory that Madotsuki is always dreaming, but this could just be a remnant of the game's engine.
Health
Madotsuki's health points can be found in the pause menu and the save windows, represented by a heart icon. 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 the 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 possible that removing health points from the game was simply too difficult.
As health can never be lost, Madotsuki's HP and max HP are always the same value.
Vending Machines
Vending machines sell pink drinks that increase Madotsuki's HP. Below are details about the three vending machines found in the game:
Dense Woods A
This machine can be found in Dense Woods A, located near the entrance from Puddle World. It dispenses a small can that costs 100 yen. The drink will add 1 HP.
Hell
This machine can be found in Hell, located west of the Nenrikido of the Face Carpet Plaza. It dispenses a medium-sized bottle that costs 130 yen. The drink will add 1 HP, and has a 33% chance of adding an additional point. This vending machine is the most cost-efficient.
Docks A
This machine can be found in the Docks A, located near the staircase from the Sewers that requires the Midget effect to access. It dispenses a large bottle that costs 150 yen. The drink will add 1 HP, and has a 50% chance of adding an additional point.
Gallery
The various health drinks.
A vending machine in the manga.
