So I was thinking: Is it just me or does there seem to be a running theme through all of these games of "Copies".
I mean, yeah, duh, game about a clone, but beyond the basic stuff with copying genes, most of the flood of examples I thought of had to do with copying the memes, jack.
Snake Eater: By and large the originator of the memes and genes as the first chronological game. But, by the end of the game, Ocelot copies all of snakes moves, and the game's tone is copied from/homage to James Bond. Also, they copied The Boss's codename when Giving Big Boss his title.
Peacewalker: Huey copied the leg designs from Granin, and Strangelove copied the AI's personality from The Boss. This was also as Zero was still active and working towards his flawed imitation of The Boss's ideals. Big Boss literally steals parts from other mechs to create his own walking battle tank, Zeke.
Phantom Pain: Venom himself is a "memetic clone" of Big Boss (as opposed to a genetic clone like the Snake triplets). Some (I think not all) parasite technology was copied from the corpses of the Cobra Unit. Skullface's unit is "XOF"; identical to the FOX Unit logo, but mirrored.
MG1&2: Don't know these well, but obvious: Weaponized a clone of Big Boss in order to kill Venom and (apparently not quite) kill Big Boss.
MGS1: Solid snake fights his evil twin. Genome soldiers are enhanced with the "Soldier gene" which was discovered through study of Big Boss's DNA. Liquid Snake eventually declares Shadow Moses to be "Outer Heaven". Game actually overtly ends with a speech about how the ideas you pass on are more important than your genes.
Sons of Liberty: The program is designed to turn Raiden into Solid Snake. He is commanded by a computer-generated copy of Colonel Campbell. Intentional or not, Solidus Snake copies Big Boss even more than Liquid does; Loses an eye; Declares Arsenal Gear to be "Outer Heaven" (if I recall). Dead Cell Unit intended to copy FOXHOUND unit from MGS1. Ocelot is taken over occasionally by a mental copy of Liquid Snake. Secret antagonist is a computer system designed to control the propagation of memes.
Guns of the Patriots: Ocelot completely transforms into a copy of Liquid. Declares his warship to be "Outer Haven". Patriot computers defeated by virus that copies FOXDIE (whatever that means). Ocelot's ultimate plan is to exploit the computer's lack of creativity in that it copies its OWN memes and uses Solid Snake as a FOXDIE vector, AGAIN. Two of the B&B fights (Mantis and Wolf) are semi-copies of the fights with FOXHOUND members that shared those codenames.
Misc/Meta: A scientist wets himself. A soldier has diarrhea. A cyborg ninja.
This ended up being a lot, and I probably still missed a lot.