
1) Fictional engineer 2) Fictional roboticist 3) Metal Gear character 4) Video game sidekick
Found on
https://www.crosswordclues.com/clue/otacon

In Metal Gear Solid, Otacon, an ArmsTech employee who designed Metal Gear REX, becomes a close ally of Solid Snake upon learning of REX`s nuclear strike capabilities. After the events of Metal Gear Solid, he helped Solid Snake form Philanthropy, a group whose main objective is to prevent proliferation of Metal Gear-type weapons. Snake and Otacon ....
Found on
http://en.wikipedia.org/wiki/Otacon
No exact match found.