Gulthias tree

A Gulthias tree was a plant infused with supernatural evil, capable of spreading corruption to nearby plant life and generating malevolent creatures known as blights. A Gulthias tree could originate wherever a plant was contaminated by an evil force or sentience.

Powers
A Gulthias tree left unchecked could infect the surrounding forest and cause blights to emerge from nearby corrupted plant life. The tree and its associated blights could turn a lush forest into a toxic, bramble-filled wasteland, growing with supernatural speed to overwhelm nearby roadways and settlements.

History
According to legend, the first Gulthias tree sprouted from the stake used to slay the vampire Gulthias of Nightfang Spire, head of the cult of the red dragon Ashardalon. The stake destroyed Gulthias, but the vampire's latent magic caused the stake to sprout, growing into a sapling infused with vampiric power. A druid was said to have later discovered the sapling and transplanted it an underground grotto, where the druid nurtured the tree until it produced the first seeds from which blights were generated.

Notable Gulthias Trees
Around 1490 DR, Grannoc, a half-orc anchorite of Talos, cultivated a Gulthias tree within a ruined manor in Neverwinter Wood, northwest of Conyberry.

Around 1492 DR, a Gulthias tree appeared along the banks of the Stojanow River outside of Valjevo Castle in Phlan, causing the magical thicket around the castle to spill into the streets of Old Phlan and generating malevolent blights.