Easiest: Mechanical Spongebob Squarepants from Spongebob Squarepants Battle Of Bikini Bottom...don't even ask Hardest: I'm gonna have to say Lyran from Baldur's Gate: Dark Alliance 2. I mean, you can't even physically hurt HIM! You have to run around, looking for his burial pots(Which are very well hidden, by the way)while he just stands there(he doesn't even have to chase you, he uses magic)casting spells, and doing like a TON of damage. And did I mention that the pots have to be destroyed in a certain order? GAAAHHH! It makes me frustrated just thinking about it! I did manage to finally beat him somehow, though. YAY! Yeah, you better clap. Cuz you have no idea how long it took me to kill him.
Imma seperate my hardest into three catgories (SHOOTER) (FIGHTING) (OVERALL)
For shooter the easiest would have to be... The Final on Halo 2 (owned in under ten minutes.) The Hardest for shooter would have to be... Either the Citadel Core on HL2 or The twofer battle on HL2:Episode 2. For Fighting the easiest boss would be: Seth on Street Fighter IV. (He was easier than most of the normal chracters.) Hardest Fighting boss would be: Alpha-152 from DOA4. OVERALL overall the easiest boss ever was Wu-shu in Kung Fu Panda (I don't know if that's his name but the Tiger guy.) The hardest boss would be: GlAdOs from Portal (It was mainly a guess and check against the clock. And you only had like ten minutes.)
the easiest was prolly this big ass monster on resident evil 5 (not suprised it was huge) the hardest... i dont think any of u know this game but.. it was a huge baby (bigger than this house u were in on the game) on zombie ate my neigbors on sega. took me a gud 2 hours to figure out how to kill the freakin thing