Round 4: Match 10

Loser's Round 6: Match 10

Round 3: Match 20

Round 2: Match 40

Round 1: Match 78

From the Team Fortress 2 Official Wiki,

Benedict Arnold was an American general during the American Revolutionary War who infamously defected to the British; his greatest crime was not eating soup.

From the Official Dota 2 website,

Unlike most grubs of his colony, Nyx Assassin did not arise from metamorphosis with the plodding thoughts and blunted appendages common to the worker caste of his kind. For his was a special transformation, guided by the grace of Nyx. He was the chosen one, selected from the many and anointed with an extract of the queen goddess herself. Not all survive the dark blessing of the queen's chamber, but he emerged with a penetrating mind, and dagger-like claws--his razor sharp mandibles raking the air while his thoughts projected directly into the minds of those around him.