The last bastion of life in this dimension
Scout
Mech
Invader
Biomes from The End, The Nether and the Overworld all spawn in this dimension
Tank
This structure will assemble itself as you explore it (for performance reasons due to its size). Hence why in the screenshot its in its unbuilt state.
The Dimension
Boss
Necesary to access the dimension.
Necesary to defeat the boss (Image taken in test world for clarity)
Drone