Lava
Lava is a dungeon feature found in places such as the Valkyrie and Monk Quests and the Plane of Fire.
Stepping into lava is dangerous. Falling into lava without fire resistance will result in instant death, while falling into lava with fire resistance gives you a few turns in which you can escape before sinking below the surface and dying. Riding a non-flying/levitating steed over lava will instantly kill your steed, destroy your saddle, and then leave you in the lava.
If you find yourself stuck in lava, you can jump out, freeze the lava with a cold attack such as by a wand of cold and then dig yourself out with a digging implement like a pick-axe (with this method you must freeze all adjacent squares of lava as well or the lava will pour into your hole), teleport out, pray, or get engulfed.
Crossing Lava
You can cross over lava using many of the same techniques as for crossing a moat, but with added attention to the burning hazard.
You can avoid contact with lava with levitation, flying, jumping, teleport, throwing an iron ball you're chained to, riding a flying or levitating pet, or polymorphing into a creature with one of these abilities.
You can turn lava into normal floor tiles with a cold attack from a wand of cold, the cone of cold spell, or a frost horn. The breath of cold attacks from monsters such as winter wolves will also freeze the lava. You can also fill the lava with boulders, but there is a 90% chance the boulder will sink into the lava without a trace.
You can also walk directly on the lava using fireproof water walking boots. Walking over lava without fire resistance will damage you every turn you do it. Even if you and your water-walking boots are both fire-resistant, other flammable objects are likely to burn if you carry them while walking on lava.
Even if you have flying or levitating, lava is not considered a safe location to teleport to by the game. Choosing to teleport when you have teleport control onto lava will deposit you on a random "safe" square instead.
UnNetHack
Lava appears far more often in UnNetHack, particularly in Gehennom in the form of both level-bisecting rivers and encircling seas. Lava also appears in Moria. A player should assume they will need to possess a way to bypass or freeze lava.
Bugs
Lava is currently subject to bug C343-231:
Time is distorted while sinking into lava.
Certain actions which do not take any time on the turn counter, such as entering an invalid extended command, will still decrement the variable which tracks how far you have sunk into lava. Thus, you may sink to your death sooner than expected, possibly even the same turn you stepped into the lava. Be careful what you do in this situation, and take action to stop sinking as soon as possible. This bug is fixed on nethack.alt.org.
Lava is also subject to bug SC343-18:
Escaping from lava can leave hero outside of time.
It is not clear what this bug was supposed to refer to. Communication with the DevTeam implies that this bug is somehow related to checks for lava effects while submerged in lava being performed at the wrong times (for instance, you can remove red dragon scale mail in lava and not catch fire even if it was your only source of fire resistance). However, they had forgotten what specifically the bug was describing.
This page may need to be updated for the current version of NetHack.
It may contain text specific to NetHack 3.4.3. Information on this page may be out of date.
Editors: After reviewing this page and making necessary edits, please change the {{nethack-343}} tag to the current version's tag or {{noversion}} as appropriate.
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