Bellator

Bellator was a Time Lord.

At the Time Lord Academy, Kenossium was mentored by Bellator, whose lessons taught her how to survive "sixteen transwarp campaigns and a Time War".

He went to the Tower of Silent Memory to select his next and last incarnation's form, but it went wrong and he was killed, alongside six other Time Lords who had died in the same way that very day. This was later revealed to be the work of Alexander Truscott and the Absence, who were working with Fey Truscott-Sade to ruin the Time Lords. Fey later showed the Twelfth Doctor footage of his death as she explained her plans to him, leaving him horrified. (COMIC: The Clockwise War)