Unknown Entity
The Queen of Peru is a monster first encountered in Peru and later in Kazakhstan, brought there by Amanda Evert by using the Wraith Stone.
The creature's past and even name are unknown; it is contained in a stone called the Wraith Stone that is found by Amanda in Paraiso. The full extent of it's powers include throwing fireballs, teleporting and merging with other beings - one who obtains the stone can have complete control of the entity.
In Bolivia - The Looking Glass Amanda will merge with the creature to form the Amanda Entity.
In Underworld
After the events of Legend, Lara keeps the Wraith Stone, but it is stolen from her by her doppelganger and given back to Amanda. Amanda later uses it to help Lara fight Thralls in the Arctic Circle level as Lara goes to find her mother.
From the official site
An unexplained malevolent entity of unknown origin, Lara first encountered it in some ruins near Paraíso, Peru where it slaughtered most of Lara's colleagues.