Rune lock
The rune lock is a barrier found on the 14th floor of the Dungeon, preventing you from travelling any deeper until you've acquired at least one rune of Zot.
Rune Availability
By the time you reach the rune lock, you'll have a limited selection of runes to go after. Here is a list of all runes available by D:14:
- Decaying - Found in the Swamp, which generates in 50% of games. Although difficulty varies based on the particular Swamp ending you encounter, this is widely considered to be the easiest rune to acquire.
- Gossamer - Found in the Spider's Nest, which generates in the Lair in 50% of games. Moderately difficult.
- Serpentine - Found in the Snake Pit, which generates in the Lair in 50% of games. Moderately difficult.
- Barnacled - Found in the Shoals, which generate in the Lair in 50% of games. Moderately difficult.
- Abyssal - Found in the Abyss, which you can access through unwielding a distortion weapon or by being banished by certain monsters. High difficulty, though less so for worshipers of Lugonu.
- Slimy - Found in the Slime Pits, which generate in the Lair in all games. High difficulty, though much less so for worshipers of Jiyva.
- Obsidian - Found in Gehenna, which can occasionally be accessed via the Vestibule of Hell found in one Lair ending. Extremely difficult.
- Icy - Found in Cocytus, which can occasionally be accessed via the Vestibule of Hell found in one Lair ending. Extremely difficult.
- Bone - Found in Tartarus, which can occasionally be accessed via the Vestibule of Hell found in one Lair ending. Extremely difficult.
- Iron - Found in the Iron City of Dis, which can occasionally be accessed via the Vestibule of Hell found in one Lair ending. Extremely difficult.
Bypassing
Currently, the rune lock may be bypassed, by a guaranteed shaft on D:14. Be aware, though: the rune lock applies both ways, meaning you will not be able to return until you acquire a rune. The available runes are the silver rune in the Vaults, the golden rune in the Tomb, the Abyssal rune, and the nine runes found in Pandemonium and Hell.
History
Although the concept of a rune lock had been debated since very early versions of Crawl, it was only implemented after the 0.13 tournament, which made acquiring a rune before D:14 an optional challenge conduct. Prior to the rune lock, players had little reason to explore the Lair branches until after they'd explored most of the main Dungeon, leaving them very overpowered for the challenges the branch endings provided.