The Beetle Lair is an ancient area located in the Realm of Outworld.
About Beetle Lair
Introduced in Mortal Kombat: Deception, this tomb-like structure is located high in the Lei Chen Mountains with Outworld. It is said that it was a place of worship for a warrior demi-god called the Death Knight as seen in the carvings on the wall. Blood beetles roam freely, and a powerful weapon known as the Thor Axe is located here.
The Beetle Lair is made up of two different rooms. The first has a beetle glass structure and two pillars, all three of which can be broken. Players can knock their opponents through the wall without a door or window, leading them to the second area. Here, an axe can be found and used by either player. Both rooms are swarming with flesh eating beetles, which were intended for a death trap, but the idea was scrapped. Instead, players can squash the bugs as they walk over them.
In a promotional video for Deception, Baraka and Mileena are seen fighting here. Given the context of their Deception endings, it is likely that Mileena won the battle and fed "Baraka" to the Blood beetles.