Lurkers in Light. They will mercilessly harrass anyone they find nearby and even kill them. Animals will instinctively flee from such grass circles, and wise explorers will follow their examples. As the Lurkers become partially visible as the sunlight fades, they will not stay after darkness. A cloud passing the sun might also reveal their presence.
When war between the First City and its Nardhome colony became inevitable, many archmages of the colony prepared for the worst and established hidden sanctums where they could regroup. This sanctum, near the Crystal Falls, was established by Zohar, one of the disciples of Nyros himself - the man who would become a god. The facility is entirely underground, covered by grass and surrounded by magically enhanced stone highly resistant to the spells of intruders. However, time and erosion have weakened its foundations, allowing ground water to seep in at the sides and half-submerging the compound. Furthermore, the bio-alchemical substances produced to this day by the autonomously working magitech have started to seep outside, which gives the grass above strange discolorations and mutations - and thus, a clue to the facility's existence. However, explorers who wish to enter through the weakened sides by digging into the ground should probably take care to protect themselves from the somewhat toxic, not to mention mutagenic waters. They didn't know about this in advance? Well, that's too bad...
The facility is protected against teleportation (as well as scrying), except for a hidden teleportation beacon. A careful search of the premises - which will require either draining the murky water or a lot of diving - will reveal numerous enchanted items useful for alchemy and bio-thaumaturgy, beyond anything the Flannish Cities can produce at the moment. The heart of the complex are five cloning vats, which within the span of four weeks would grow clones of creatures whose blood was inserted into them via a special receptacle - and if the original were slain, their souls would automatically enter the clone. However, only one of these vats still works (and it might produce odd mutations in the clones, given its age). The others were heavily damaged ages ago, and have malfunctioned and broken open. The malfunctioning vats have produced two gibbering mouthers, which hibernate in the murky waters most of the time but will awake there is a lot of activity near them.
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