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teleportation hub room can yield a map that traps the hero by making stairs inaccessible #1640
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- linked a pull request that will close this issuethemerms: keep Teleportation hub traps off the wall-adjacent gutter #1641
on Jul 26, 2026 The only way out I can think of is try to camp until you kill enough stuff to reach level 5 (starting with your pony, may give you level 3 right away) and then wait for a rock mole. (or a dwarf with a pick-axe). You are likely to fail a food prayer before that happens, though.
Duplicate of #805
Normally there's a 20% chance to "escape" a trap when you step on it, but 89ea47f specifically makes traps in hubs unavoidable. If not for that, davidbau's situation would be merely annoying rather than game-ruining, so reverting that change could also be a solution.
When random traps normally generate in rooms, they avoid spaces next to doors for reasons just like this. Traps randomly placed in themed rooms currently unfortunately avoid this logic, since with ordinary rooms the traps are placed after we know where the doors are, but in themed rooms the traps are placed before rooms are connected and any doors exist.
A narrow solution is possible for this specific issue, since the teleportation hub actually does create its traps after the rooms have been connected. That would entail passing the room selection as data to make_a_trap, and removing any spots adjacent doors from it, before picking where to place the teleportation trap.
But it is probably better to find a general solution for avoiding traps in themed rooms next to doors.
When random traps normally generate in rooms, they avoid spaces next to doors for reasons just like this.
Are you sure? I don't see a
bydoor()check inmktrap(). Even if teleport hubs will obey this restriction, evidently it could still be possible (although unlikely) for those three traps to cordon off the door anyway.
I think the teleportation hub themed room can make the stairs on their level inaccessible. Screenshot:
In this map, all three teleportation traps teleport to the left two rooms in the level and there are no paths out. I encountered this at Dlvl 3 with no way to dig or disable or jump over or circumvent these traps. Maybe I'm missing some possible gameplay trick to get out, but it feels like a boring game just being stuck in three rooms, and it doesn't seem very NetHack-like.
Do (or should) teleportation hubs have some logic to avoid creating inaccessibility traps like this? Maybe teleportation hubs should avoid blocking the doorways?