First, let craft some quick random tables.
Labyrinth's nature (d6)
- Natural network of caves.
- Crafted by giant ants or termites or other burrowing creatures.
- Crafted by an ancient human civilization using long forgotten magic or tech.
- Crafted by an ancient near human civilization (dwarfs, trolls, elves, etc).
- Crafted by an ancient non human civilization (myconids, demons, neo otyugh, etc).
- Divine creation, crafted by an ancient divine entity.
- Single path
- Single path, with two complications
- Two paths
- Two paths, one with two complications
- Two paths, both with two features
- Three paths, one with two complications
Path's Complications (d6)
- Partly flooded
- Very warm or cold
- Infested by a swarm of creatures
- Lair of a large and dangerous creature
- Sealed a long time ago (locked doors that seal forgotten rooms and dangers)
- Trapped (natural or artificial hazards)
Path's feature (d6)
- Precious mineral, fossils or gems veins
- Concentration of magical resource
- Rich underground fauna or flora
- Wards against dangerous underdark creatures
- Carved maps or sign posts
- Inhabitants (see table below)
- Criminals, smugglers and bandits secret lairs
- Outcasts and refugees communities
- Guides safe houses
- Trade post or community of humans and underground species
- Guild houses (cartographers, geologists, prospectors, etc)
- Military outpost or Knight Order fort holding up against underdark creatures
Now let establish 3 land masses and why their seas are hard to navigate.
- Northern Lands (sea is often frozen)
- Southern Lands (sea plagued by giant sea serpents)
- Eastern Lands (frequent storms and tsunamis)
The North-South Labyrinth
- Crafted by an ancient human civilization who used forgotten geomantic magic.
- A single Path that is the lair of a large creature and that feature ancient magical wards.
- Natural network of shimmering crystalline caves.
- Path 1: Infested by a swarm or creatures attracted by a concentration of magical resources
- Path 2: Very cold and feature a community of underdark creatures and humans denizens.
- Path 3: Trapped by magical radiations and precious fossils
The South-East Labyrinth
- Crafted by an ancient non human civilization of lava dwellers.
- Path 1: Partly flooded and lead to several pirates and corsairs hideouts
- Path 2: Partly flooded, very hot, crossed by a magma river but also rich in gems