Fountains can produce both good and bad effects when (D)runk from, each effect triggering its own special message. It is entirely up to you whether or not this is worth the risk.
You can also fill empty bottles or cans with water from fountains by dipping them ('!' command), but bottled water does not retain the fountains' magical properties.
Drinking from a fountain can alter your attributes and status effects. You will see one of the following messages:
This water tastes good.
You get no special effect, just slight satiation. Thus drinking water from fountains can save you from starving if you have absolutely no food.
This water tastes very good.
A random attribute of yours has just been raised by one.
This water is contaminated!
One of your attributes has just been lowered by one.
This water tastes good, but has an odd after taste.
You gain a temporary magic effect, as specified by one of the following messages:
- Slow - "Everything seems to move much faster now."
- Haste - "Time slows down to a crawl."
- ESP - "You suddenly feel like being only a tiny part of a great network of intelligent minds."
- Telecontrol - "You feel very controlled."
- Teleportitis - "You feel jumpy."
- Polycontrol - "You feel you have complete control over your body."
- Polymorphitis - "An uncomfortable uncertainty of who you really are overwhelms you."
- Invisibility - "You feel somehow transparent."
- Infravision - "You feel your perception being magically altered."
- Gas Immunity - "All smells fade away."
- Levitation - "You rise into the air like a small hot-air balloon."
This water tastes very odd.
Same as above, only the effect is permanent.
The following effects can also rarely occur while drinking from a fountain:
- A female dolphin is summoned.
- A genie is summoned. It can be either hostile or friendly, in the latter case it will grant you a wish and disappear.
- Several snakes, mommo slimes, dark frogs or large rats are summoned, either hostile or allied with the player.
- The fountain will spawn one of the many different types of rings.
- You gain a random disease.
- A mystic dark frog is spawned somewhere on the level (only 1/1600 chance).
- You are sucked into the fountain and pulled through the pipes to another fountain in the dungeon. This effect can 'teleport' you even to a completely different floor, even one not yet visited.