Skagra

Doctor Skagra was a Geneticist, Astro-engineer, Cyberneticist, Neurostructuralist, and Moral Theologian from the planet Dronid.

At some point he departed Dronid and set up Think Tank with the aims of creating a sphere capable of draining minds and adding the contents to its database.

Following the creation of the Sphere he set out to search for Shada and Salyavin (he most likely found out about Salyavin from one of the Time Lords on Dronid).

Skagra wanted to 'possess' the universe, and for this he needed Salyavin's ability.

Skagra travelled to Earth to find Salyavin. While, there he obtained a copy of Professor Chronotis' mind and The Worshipful and Ancient Law of Gallifrey, the key to Shada.

Skagra was left trapped within his sentient ship following the Doctor's alterations to it. (DW: Shada, WC: Shada, BFA: Shada)