The Robust Twilight Oak is a tree added by Twilight Forest. These trees spawn naturally in most biomes within the Twilight Forest dimension. The saplings can only be obtained inside of Leaf Dungeons. Robust Twilight Oak trees are 3-9 blocks in diameter, though they are hollow and filled with vines, and can be anywhere from 50-100 blocks tall. They can sometimes spawn Leaf Dungeons on top of them. These trees are the only source of Cicadas apart from loot chests.