Cosmos (Andu Supplement)
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To see a citadel in the middle of a forested area, one would think that Elves live there. This couldn't be further from the truth. A knowledge (nature) check would reveal that the forest consists of only Darkwood trees. Four small unguarded keeps also protrude from the ground that appear to be exactly a mile from the main building.
There are four keeps, one to point of direction (north, east, south, west) rising up 40 feet with a 20 foot square base. The doorway is large enough for a human but bigger creatures must duck and feel cramped inside the structure. A spiral staircase descends into the earth to a carved corridor 10 foot wide by 10 foot high. Characters seem to be going down an endless stairs until they finally reach a stone platform with another doorway. A corridor heads away from the keep towards the citadel.
After about 1000 feet of tunnel, the surrounding walls and ceiling open up to a large cavern. The corridor becomes a land bridge suspended over an excavated pit. There is no natural light in this cave but light spells may reveal the dimensions. The ceiling is over 200 feet up, the sides are close to 3 miles in diameter, and the pit below is at least 300 feet. At the point where the cave walls open up from the corridor, a successful check will reveal that this opening was formed by mining tools.
As the characters get closer to the center, the 'bulb' like mass of earth and building appears before them. There are three other land bridges meeting the base from the other keeps. So far, the keep, corridor/land bridge has been carved from stone (in case a spell requires sand or dirt).
Entering the Citadel from either corridor/land bridge places the characters at the bottom level of the citadel. This bottom floor is a square mile of mazes meant to confuse those who have managed to wander to this point. If the intruder is unwelcome, a number of servant minions could be unleashed upon unsuspecting foes.
The layer above this one has an open area in the middle to catch groups in area effect spells. There are quite a few layers to this Citadel considering the trip down was rather long. The DM can add whatever they wish to fill this area in. There is at least one secret spiral staircase on the bottom or second to last level that avoids all other layers. This allows trusted individuals to enter in a hurry.
This area is rather open having many rooms with vaulted ceilings. A successful spot check will reveal small passages on the peaks of rooms that lead out and may connect to other rooms. A fleeing character with a fly spell might use this to avoid combat should the need arise.
In the 'heart' of the Citadel is a grand chamber with a stone platform of orange-yellow color. The platform is 20 foot in diameter and raised about a foot from the surrounding stone. It gives off a brilliant light, with some of it being reflected and the other an iridescent glow from within. A successful check may reveal that the stone is actually a large amber gemstone.
Another successful check may reveal that amber is formed by fossil tree resin and this partucular amber was made from Darkwood trees. True amber is relatively rare though the price hasn't been effected since copal is usually passed off in its place. The value of this gem is unmeasurable.
Should characters be allowed to stay or even given free will to walk about, there are some notable features. There is a small barracks to hold troops though by some of the graffiti on the walls suggests mercenaries were used. Other rooms include a kitchen, wash room, study, library, dining hall, and a stable. A number of empty spare rooms have been recently cleared though each one is called a 'provisions' room.
Guest quarters are located on the second floor of the main spire. The high wizard's chambers is also on this level with some smaller quarters for apprentice wizards. Continuing to the top floor leads to a small balcony with no railing.