Assistant Director Aaron Wilson is a greedy member of The Shop and the secret head of Prometheus. Missing the old days of the Cold War, Wilson decided to bring it back by using his old contacts in KGB to create Prometheus and have them develop a deadly Romulus virus, which he soon tested by forcing drug lord Manuel Vergara to sell it to a rebel terrorist group La Fuerza del Dios and led them to use it on a village full of innocent people, leading to many people dying a slow and agonizing death. Later on, leaking The Shop's moves to Prometheus and blowing up a secret base under the book shop, which caused several deaths, Wilson has Prometheus attack a hospital to kill the survivor of the explosion. At the end, abandoning all pretense, Wilson leads an attack on The Shop, killing countless people and openly announcing his intention to use the Romulus virus to infect world leaders and plunge the world into another Cold War.
Ex-KGB agent Alexei Nachrade is one of the highest members of Prometheus, acting as its official leader. Eagerly joining Wilson's scheme of using the Romulus virus to plunge the world into a Cold War, Nachrade takes an equal part in trafficking the virus to US territories and delivering it into the hands of La Fuerza del Dios for testing. When John Mullins starts getting too close to discovering the identity of the mole within The Shop, Nachrade has him lured to Japan to his personal prison, where he has his men torture people to death. Later on taking the airport full of people hostage and having his men murder several innocents along the way, Nachrade distracts Mullins enough for Wilson to attack The Shop, announcing that with The Shop destroyed nobody could stop Prometheus from doing whatever they want.
Difficulty Spike: The Colombian jungle. Terrorists concealed by bushes that they can see through fine, assault rifles come into play, and as mentioned above in Demonic Spiders, they can magically see you and lob perfectly-timed grenades over hills that you didn't even get close to. After you're done with it, though, the difficulty (or at least the Grenade Spam) drops back again until Kamchatka, near the end of the game.
"Funny Aneurysm" Moment: One of the levels has Saddam Hussein in it (he only appears in a cutscene), through cheats however, you can spawn and kill him. Now try to play this game now that Saddam is dead for real.
The final boss of the first game is regarded as this by many, with an extremely powerful weapon, nasty turret back-up and being absurdly resistant to everything with the Handwave of "he's wearing body armour".
The Interrogator in the Hong Kong prison in the second game, with his near-instant-death machine gun. And he's Made of Iron even though he doesn't wear armor. The real boss, Deviant1, has a Sniper Rifle and WP grenades, but isn't anywhere near as dangerous as he is.
The Final Boss in the second game is an Osprey that'll rip you apart in seconds if you're out of cover and takes an insane amount of ammo to bring down if you don't know what you're doingnote shoot the engines' outer panels and their glowy insides until both catch fire like back in the hospital, and then shoot the pilot. This is the one time where the OICW's alternate launcher actually comes in handy: if you can adjust the range properly, you can lob grenades at the chopper safely and defeat it much faster then you would with normal ammo.