Lara Croft. Classic Lara Croft is that Randy is thinking of but can't seem to put his finger on, before Crystal Dynamics pussified (not pun intended) her into a "more deep and realistic character" she was truly ego-centric and independent bad-ass.
The only two people in here life was a subservient butler and her former mentor who became her mortal enemy for being too much competition.
Lara may have been more sexually alluring throughout the first 5 games but she was a cold-blooded badass and never fell victim to any feminine weaknesses such as seduced to trusting a man.
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TL;DR While I think a central-tenant of Duke Nukem is is satirical ego-centrism you you change too much with a complete gender inversion.
What if it was just a gender inversion, not "female equivalents" but a pastiche of all the Female-badasses of pop-culture from Ripley to Samus Aram (pre-other M) to Sarah Connor to most of the female Street Fighter characters.
I think Sarah Connor would be the closest superficially but her character was defined by her unwavering motherly love for her son and a certain inner fragility (that stopped her murdering Dyson). if Duke Nukem was compelled to kill miles Dyson in Terminator 2 he wouldn't have been overcome by guilt, he would have just said a funny quip and blown him away.
See there is such a lack of ego-centric female characters in games, films or books that doesn't come across as just a manipulative ***** who is ultimately unlikable.
I suppose Scarlet O'Harah of 'Gone With The Wind' was self-centred but while that comes across as endearing in a male character it is despairing (yet dramatic0 in a female character.
I'd like to see Gearbox do that, make a female character that is:
-supremely confident, independent and capable
-utterly self focused and internally motivated by own personal needs
-completely un-phased by the wrongs around her
Hang on a minute... this sounds familiar:
What have i been saying, there has been a female Duke Nukem for longer than there has even been a Duke Nukem, Lara Croft appeared in this form in 1996, a year before Duke Nukem went 3D and became the character he is known today. I'm talking classic Lara, not this new "ooh, i'm not a murderer am I?" that crystal dynamics tried and failed at.
She has gunned dozens of species to extinction, decimated primitive tribal communities, murdered her competitors in cold blood for what? To save the world? Only tangentially, her primary motivation is adding some relic to her own private collection simply for her own aesthetic desires and lust for power.