I only read up to page 11, so this might be covered already,
Is it just me, or are the final boss levels in the Doom games seemingly impossible. I honestly don't that the developers intend for you to beat those without cheating. There's just no way.
Also, while I'm in FPS mode, Beating the WAR! mission in Perfect Dark on Perfect Agent is also extremely tough. I still haven't done it. And finally, the Primagen from Turok 2 was pretty tough.
I'm not sure if anyone has mentioned this either, but certain RTS games can have intense "boss" fights. One incident comes to mind in Command and Conquer: Tiberian Sun - Firestorm. The last mission where you have to destroy CABAL's Core and the Core Defender comes online. You spend hours fending off the enemy and doing your best to build and maintain your base while you make progress through the different battles. Suddenly, when the Firestorm defense goes offline, this previously unasuming pile of pipes and metel unfolds into a giant cyborg and just plows through your army, gets to your base and destroys it. I could never save myself from that thing no matter how I prepared for it. Finally I got the bright idea to send about 50 hovercraft mobile rocket systems undernieth the bridge that led to my main base. I unleashed everything I could on that bridge as the Core Defender walked over it. The bridge collapsed and the big thing went strait into the drink. I just blew up CABAL's Core after that and felt really proud.
