Elkonia: Phantom Keep
A rare dungeon keep with twelve boss encounters, puzzle rites and a deserted ward village. There were seven keeps; six remain. The seventh was lost, and has been seen in many places since.
The arena
Where the summoned come up. Every boss has its own moveset, staged at two thirds and one third of its health.
The Household Guard
Kill Gus, the last name on the household list, and the machine built to protect that list comes to ask who you are.
Phantom Keep from Above
The mid wall, the tower and the ward village between the walls. Keeps generate roughly 12,000 blocks apart. The village inside it's walls is haunted and guarded. Kill Bacon, and Gus to have a boss fight or two. There are several puzzles awaiting you.
The Creeking Awaeksn
one of the 12 bosses, the Creeking. You'll have to solve the puzzle to summon him.
The main Keep on the insides
A large area to fight a boss maybe? Sound the bells to make the chime, in time.
Alter
If you win a named item from a trial spawner or vault, place it on the alter, a new challenge may ensue.