Zilla Fortress is a location featured in Shadow Warrior (2013).
The fortress was a giant structure built in high in the mountains under orders of Zilla. Because of demon invasion the construction is only semi-complete. Zilla has a mansion on top of the mountain. There also various labs located inside the fortress, the purpose of which isn't revealed. When Lo Wang kills the second Whisperer, he's transported to the fortress. There he reaches Zilla, where after a tough fight he escapes with the third part of Nobitsura Kage.