What follows was recorded in a Twin Journal by Theosian operatives, acting against the Tyresian empire.
“It tooks weeks of effort to discern the pattern to the supply ships. Once we had it figured out, we stowed ourselves into the cargo and used magic to conceal our presence. It is unfortunate that we could not conceal the smell, for the ship was loaded with offal, and what appears to have been executed prisoners. To what end this hideous cargo would be used, we did not know.”
“After a revolting journey which seemed too long - the ship took the most torturous path to the Island all the while with the cargo ‘ripening’ - we finally made landfall. We quickly found out what at least part of the cargo was for - the ships were being unloaded by dozens of walking dead. Fortunately our sorcerous guises held and we were able to slip onto the island proper, and establish our hidden base camp.”
“The island is covered with trees of the most excellent quality and surprising uniformity. The trees stand in straight lines like well-drilled soldiers. They stand tall enough to supply single masts for even the largest ships in our navy.”
“Our base camp we established with the greatest care in its concealment - the island is heavily populated by the walking dead , and the occasional heavily armed patrols of veteran soldiers made for many an anxious moment. The use of undead is atypical of our enemy - normally they are almost excessively above-board even in warfare. It shows a darker side we did not expect and highlights the importance that this island is held.”
“Over the next few days we carefully observed the tree farming aspect of their operation. I must use this word, no matter how odd to describe it, for never have I seen trees treated thus. What is also apparent is the trees grow at the most extraordinary rate ! We measured several near our camp and found that growth in the order of an inch a day was typical. This incredible rate indicates that this island could produce excellent masts in a few years as opposed to the generations it normally takes. It is little wonder that our enemy can always field more ships then us - we must find some way to either replicate their success or destroy this island!”
In an age of sail, one of the most important of resources is a source of tall, straight and strong trees for use as masts. Mastwood island is one such location.
As an important strategic resource, this large island is well away from any commonly travelled seaways, and is best located in areas which are fraught with natural hazards.
The first line of defence is secrecy - it is a closely guarded secret whose location is known by only a few trusted captains and is not written on any map outside of the Emperors personal vaults. (This is kept as an emergency should all of the captains perish in some calamity).
The second line of defence is it’s remoteness and location. It is located in a Naval Reserve Area where no civilian ships are allowed - violaters are liable to received the harshest punishment that the empire condones and ships are always seized. Naval ships are almost always nearby ‘on exercises’ though they are carefully controlled by the naval brass to avoid getting to close to the island.
The third line of defence is that the shoreline of the island has been carefully modified to deny easy landing for most of it’s circumference - rocks below the water line have been shaped and sharpened, beaches removed so that sheer rock faces meet the waves, etc. The only good landing point is covered by several powerful fortifications carved out of the natural rock and concealed both by plants and magic.
Basically it is a well hidden and defended tree farm.
While scraping up corpses to send to the island, Emperial operatives happened to send the corpse of someone Important by accident. Although the person in question was a member of the government, inquiries by the family as to the location of the body (for burial, resurrection, whatever) are unanswered, or worse, met with “You don’t want to go there.”) Friends and co-workers of the victim try to help, but are stonewalled by a vail of secrecy. The PCs are contacted to find out what happened to him, and their investigation may lead them to the island. What happens next, well..
The Secret Facility
A secret within a secret. The isolated, hidden nature of the island suites it well for a site of banned, or illegal experiments in areas some branches of the government would not like discovered. A separate branch of the government somehow found out about the facility and wants it shut down before it gets discovered by someone else and causes a scandal. The PC’s are contacted as independent operations to allow for their actions to be disavowed.
Additional Ideas (3)
The island is garrisoned by an oversize Cohort of veteran soldiers (1000 men), all trained in forest and marine combat. The tours of duty are long - a full year, and 1/2 the cohort is rotated out every six months. The troops are brought to the island via a long and convoluted route, and are kept below-decks the entire voyage.
The Garrison is based in a secure walled compound large enough to be partially self supporting with farms and livestock. The walls serve to protect the garrison from the various creatures wandering the island.
Patrols generally consist of no less then 20 well equipped soldiers with additional spell casters.
The trees on Mastwood island are the sole surviving product from trade that existed between the Empire and the strange and dangerous people known as The Rephatians.
The Rephatians are a strange and little known people, with a powerful affinity for the workings of life. They will be the subject of further submissions in the not-so-distant future.
They grow at an incredible rate and produce a strong, tall and straight tree. They do have a huge impact on the soil and require significant fertilizer to maintain growth. If sufficient nutrients or water are not provided for an extended period - 3-6 months, the trees will turn inwards for nutrients and the strength of the wood will be greatly decreased. For this reason, these trees cannot occur naturally.
Depending on the desired size, the trees reach full growth within 10-20 years. After reaching full growth, they must be harvested quickly or they eventually will grow too high. At some point, the weight of the tree will exceed it's own ability to support its weight and the tree will snap.
The Mastwood trees occasionally suffer from a growth defect which causes severe internal stress to build up within the trunk. This will continue until the stress reaches the breaking point and the trunk explodes - sending sharp splinters in all directions. This can be detected by careful examination of the trunk, but touching a stressed area is liable to trigger the burst.
In addition to the military garrison, the island is defended by the Necromancer Kazarad the 3rd and his entourage of undead. The Empire normally does not sanction the use of necromancy, but the unique requirements and high secrecy of Mastwood has allowed for special permission. The use of undead and dealing with the Necromancer is a closely held secret within the Imperial council.
Due to the gradual degradation of his undead, the corpses of executed prisoners, disaster victims and others are occasionally shipped to the island along with the vast amounts of fertilizer needed to supply the trees. Kazarad makes use of these corpses to increase and replace the undead patrolling the island. The undead are commanded not to attack those in Imperial livery, but they do not always obey - which makes life interesting for the human garrison of the island.