| The corridors of the Snake Pit are home to all varieties of serpent, and are inhabited by a society of powerful nagas and salamanders.
The Snake Pit is four levels deep and contains the serpentine rune. A dungeon features only one of the Snake Pit and Spider Nest branches. If the Snake Pit is present, the entrance is located between Lair:3 and Lair:6.
The Snake Pit is one of the five branches accessible through the Lair. Those who explore it are rewarded with the serpentine rune of Zot, but must deal with the many snakes, nagas, and salamanders that call these halls home. The Snake Pit and the Spider's Nest are mutually exclusive; if you come across the Snake Pit, the Spider's Nest will not generate in your current game.
The Snake Pit's layout is very variable; floors can range from collections of small square rooms connected by doored hallways to wide open areas, occasionally spotted with bodies of water. The walls of the Snake Pits are made almost entirely out of rock, making digging easy. It most closely resembles a collection of generic floors from the Dungeon, though it cannot host some of the more exotic Dungeon vaults and layouts. Like the Shoals, this branch occasionally generates shops, though this is by no means guaranteed.
Snake:4 will always contain a stone-walled, heavily-guarded rune vault which is drastically different from the rest of the Snake Pits, but the specific design will vary from game to game. This vault will take up a large portion of Snake:4, but the rest of the floor will generally be made up of simple rooms and hallways.
As with all rune branches, entering the Snake Pit when you first encounter it is not recommended; few characters will be ready for the many threats found within so early in the game. Survival here requires preparation for a fairly wide variety of damage types. First and foremost, all nagas and nearly all snakes will be capable of poisoning you, making poison resistance strongly recommended if you don't want to be constantly losing HP or burning through your potions of curing. The Cure Poison spell is certainly helpful, especially by escaping poisoning red status, but does nothing against direct poison damage, which a few monsters here are capable of dishing out. Strongly consider delaying entry until you've acquired a reliable source of this resistance. It's not technically required, but it makes things much easier.
Fire and electricity resistance are also surprisingly helpful. The many salamanders you encounter are capable of dealing fire damage with their standard melee attacks, and some come with fiery ranged attacks as well. Keeping up at least rF+ at all times is recommended. Even worse are the shock serpents. Left unchecked, these pests are deadlier than electric eels at range, and are even worse when handled in melee, countering your melee attacks with unavoidable electricity damage. Although they aren't especially common, having a piece of rElec jewellery to swap in as needed is very useful.
By far the most dangerous opponents you'll encounter here are the various naga bands wandering each floor. All are capable of hitting you with Spit Poison at range, and can constrict you in melee (making them extremely dangerous for low-AC characters to tangle with), but each type has its own unique strengths that must be taken into account. They also come with a wide variety of weapons, ranging from measly clubs to heavy 2-handed polearms. Read up on their individual pages for strategies, and pay attention to the exact composition of the band you face before acting. Also, when encountering naga mages and greater nagas, feel free to let them haste themselves and then lure them away from their allies. It's much easier to take them out in waves than all at once.
Beyond the nagas, salamander bands can be a serious threat if you lack fire resistance, and the various snakes, while easy individually except anacondas, can complicate fights with other foes. When facing both snakes and nagas, take advantage of their speed difference to lure the snakes into battle somewhere safe while the nagas slowly catch up. This may not be an option when dealing with guardian serpents, however. When these opponents are present, expect enemies to be blinking into encircling melee range with you regularly.
The bottom floor of the Snake Pit will always contain a large, heavily-guarded rune vault. There are seven possibilities:
- Three Stairways (snake_hunt): One of the nastier rune vaults, this vault's entrance chamber is filled with a variety of nagas, including greater nagas and guardian serpents, as well as three upward staircases and some known, permanent teleport traps. Because of this, players often find themselves out in the open facing several dangerous enemies as soon as they enter the floor (though due to the fact that one of these staircases may be an escape hatch, there may also be a normal staircase leading to another part of the floor). After clearing this chamber, there are several narrow hallways and small chambers densely packed with further guards, with the rune located all the way in the back.
- Serpent's Egg (snake_pit): A large rectangular chamber with an oval stone chamber in the middle, open at the top. The entire chamber is heavily populated with nagas of all sorts, and the rune can be found resting against the inner wall of the "egg".
- Caduceus (minmay_snake_end_coiled): This vault consists of a large rectangular block with a straight hallway running through the middle and a winding hallway weaving back and forth over the central. All along these paths, nagas of various sorts will be waiting. The winding hallway eventually ends in a narrow, heavily-guarded chamber containing the rune, as well as several greater nagas. This is by far the easiest rune vault, as almost any character can lure the guards out one or two at a time, eventually clearing their way to the end.
- Naga Fortress (snake_pit_salamanders_mu): The most elaborate of the Snake:4 vaults, this consists of a large trapezoidal stone structure taking up roughly half of the floor. Accessed from either the right or left corner of the structure, it consists of a series of hallways weaving back and forth over each other, eventually ending in the rune chamber. Each chamber contains a variety of nagas, and most also contain some lava with a few salamander mystics or lindwurms. However, the wide door to the final chamber instead hides anacondas and many other snakes, including shock serpents. To avoid being immediately swarmed, disintegrate the door from a distance and take them out as they approach.
- Spirals (grunt_snake_rune_spirals): A large corridor with two spirals branching off in each direction, guarded by various nagas and some guardian serpents. There are no chokepoints or sharp corners, but if you're stealthy you can pick off one or two nagas at a time. One spiral will contain the rune and the other will contain an acquirement-level item (or occasionally a rune mimic!)
- Pools (grunt_snake_rune_pools): This vault is filled with pools and sea snakes. Open opening a wide door you will find a small chamber with various snakes and a few nagas. Beyond this is another chamber with more nagas and sea snakes, and the final, larger chamber which contains similar threats.
- Serpentine Throne (grunt_snake_rune_serpentine_throne): A well-guarded snaking corridor leads to a large throne room filled with nagas. The rune is at the very back.
Note that salamanders are uncommon in these vaults, with the exception of the fortress.
- High AC and EV
- Poison and fire resistance at all times, electricity resistance as needed
- Blink or teleport (to escape constriction easily)
- Teleport control (for safe escapes and stealing the rune)
In 0.17, the Snake Pit was reduced to four instead of five levels, just like the other Lair branches.
The monster set for the Snake Pit was greatly expanded in 0.14, adding salamanders, salamander mystics, naga sharpshooters, naga ritualists, shock serpents, mana vipers, and Vashnia. Lamia was also removed.
Lamia was first introduced to the Snake Pit in 0.12.
Prior to 0.10, nagas were unable to constrict you, making the branch much safer for melee characters.