Scaroth

Scaroth, also known as Count Carlos Scarlioni and Captain Tancredi, was the last of the Jagaroth and the saviour of his species. He was also the pilot of the Jagaroth ship that landed on Earth in prehistoric times.

Humanity
Roughly 400 million years BC, a Jagaroth ship piloted by Scaroth landed on Earth. Despite his ship's advice, he launched at warp 3. The ship exploded. In the control cabin, Scaroth was splintered in time.

Twelve fragments of him were scattered across time, though they could communicate through telepathy. The explosion allowed the radioactivity that the primordial ooze needed for the human race to exist. Throughout time, his selves pushed the human race forward, showing them fire, inventing the wheel, mapping the stars, and ordering the pyramids built, so that his twelfth self could have the technology to go back in time and prevent his splintering in time as well as the death of his race.

All of his selves, except for the Egyptian self, who appeared as a god on one occasion, disguised themselves as humans using a mask and skin into which he was able to fit himself. (DW: City of Death)

Captain Tancredi
In Florence, Italy in 1505, Scaroth appeared as a human named Captain Tancredi. He convinced Leonardo da Vinci, a human painter, to paint six copies of his famous painting, the Mona Lisa. He stored them away for a later self to find. (DW: City of Death)

Count Scarlioni
His twelfth self was Count Carlos Scarlioni, a well known figure in the art world in 1979. Thanks to him, genuine art works that had been missing for centuries, like several Gutenberg Bibles, started showing up. He was married to Countess Scarlioni, who never knew who he really was, thanks to little gifts every now and then and a little "excitement". He also gave her a micromeson scanner and asked her to wear it always.

Thanks to his other selves, he used the artwork to fund his experiments with time, run by Professor Fyodor Nikolai Kerensky. Having found the other six Mona Lisas, he planned to steal the one in the Louvre.

He would then sell them to the seven people in the world who would pay anything for the Mona Lisa, and since the one from the Louvre would be stolen, they would all think they had the original, and Scaroth would make a hundred million dollars off of each.

He met the Fourth Doctor and Romana II when they tried to find the crack in time that his experiments had caused. Romana was captured and made to build a field interphase stabiliser to make the artificial time field Scaroth had created stable, allowing him to travel back in time.

Having been convinced by the Doctor and by pictures of Scaroth's true self, the Countess turned against Scaroth. He used her bracelet to kill her. Scaroth travelled back in time to try and stop the explosion that splintered him across time.

The Doctor got there first with Romana and Detective Duggan. Duggan knocked Scaroth unconscious. His time came up and he faded back to 1979. When his servant Hermann saw his true form, he attacked Scaroth and he was destroyed along with his time field. (DW: City of Death)