The main bad guy in the third Batgirl of Burnside collection, Mindfields. Memory manipulations and injection, somewhere between the Inception movie and gaslighting/psychological abuse. Not easy to use in tabletop RPGs, mind.
The most interesting ally of Mark Hazzard in the Merc 1986-87 comic book. Streetwise young expert in the Japanese martial arts, as was the style of the day. Best read after the Mark Hazzard character profile.
Gil Jourdan is a minor but classic character from French/Belgian mystery and adventure comics. This two-part profile explains a bunch of things, and covers much 1950s/1960s material.
The second half of our Gil Jourdan character profile, to avoid overlong articles. Classic — if B-list — investigation and adventure hero in 1950s/1960s European graphic novels. The first Gil Jourdan character profile is there.