Bone Tree (3.5e Environment)
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This environment is typically a forest, an evil, skeleton-filled, dangerous forest with flesh craving trees. The wood from these trees is highly sought after by necromancers, death-cults, sentient undead, and others who deal with death on a regular basis. Surprisingly, the tree loses all true-evil connotations once it is cut down and the stump is destroyed; this means that the wood can be used by anyone. See below for bone wood crafts.
 Bone Tree
A bone tree is the result of a seed being infused with necromantic energy either deliberately, as the result of some traumatic event, or from the seed of a greater bone tree. If it is deliberately made the creator must have a hefty supply of bones on hand to feed the tree as it grows. Most non-deliberate bone trees grow in soil that has been drenched in the blood from a massive battle where the bodies were left to rot and the bones eventually became part of the earth.
- Bone Seeds are hefty balls about the size of a coconut that sprout into a bone tree. Lesser bone tree status is achieved within 6 months of sprouting. Greater Bone tree status is achieved in 50 years
- Lesser: Undead within 30' gain a +2 Profane bonus vs turn attempts, corporeal undead gain fast healing 1. Animates anything dead within 50' into a skeleton within 1d4 hours. These effects do not stack no matter how many trees are together.
- Greater: Same as lesser plus the following - anything dead within 30' of the tree is animated as a skeleton in 1d4 rounds. Corporeal Undead within 50' gain a +1 Profane bonus to attack and damage when doing unarmed/natural attacks. Fast healing is increased to 5
Any species of tree can be a bone tree as long as it was affected by one of the processes described above. Some trees have no outward appearance betraying their status (the bones are around the roots or deep within the trunk), most have obvious bits of bone sticking from the bark, the most profane trees seem to be sheathed in a bony coating. Bone trees that grow from the seed of a greater bone tree resemble the original tree but with a malignant, evil twist to the orignal form.
 Bone Tree Skeletons
The first thing a skeleton does when created by a Bone Tree is tear any flesh left on its body and place it around the trees roots as fertilizer. Skeletons created by Bone Trees typically stay within 300' of the tree and retreat to the tree for healing if injured. When not defending the tree from a threat, the skeletons tend to the tree and maintain the grounds around it. Part of this maintenance is that the skeleton brings any fragments of bone it can find to the tree for integration into the tree. The trees skeletons are also responsible for the spread of the bone tree forest and they do this by taking bone seeds out 40 to 60 feet away from the tree for planting. Most trees only maintain a force of 10 to 20 skeletons, more useful skeletons are kept and other skeletons are integrated into the tree.
 Bone Wood Crafts
Some versions of the crepitus crutch are created using wood and bone from bone trees. Crepitus crutches made completely from materials gathered from a bone tree grant their created skeletons a +2 profane bonus versus turn attempts.
It is possible that the profane bone or wood from a Bone Wood Tree is useable in other crafted items. This would be at the DM's discretion.
 The Forest
A bone tree forest is a thing of beauty, the skeletal minions of the trees keep the grounds around their tree in pristine condition. The trees, while not truly intelligent, seem to be aware that a pleasant environment is more likely to attract good-aligned intelligent species. To this end, when the skeletons are not actively working they are directed to hide from sight however possible. They typically hide either in nearby large trees, ready to leap down on unsuspecting victims, or buried in the ground ready to rise up on unsuspecting victims.
You can generally assume that no tree is within 50 feet of each other and calculate how many trees can be in any one forest based on this assumption.