The hardest enemy I'd say is... hunters... even though they're still not hard... unless they come up behind you and jump or something...
And the hardest boss is... well the bosses are all so fricken easy... even the tyrant... But I'll just say... the plant... cuz the first time I met yawn, I didn't even fight it... and the second time I met Yawn, I didn't even get bitten by it... of course, that was on easy
and the plant... the first time I fought it I didn't notice it sometimes had a shell around the part you're supposed to hit... and it knocked me off the ledge a couple times... and spit on me... plus I was playing as Chris so I only had a shotgun...
Neptune? That's the shark, right? All you do with that is push the thing in the water and pull the switch ZAP... I was even reading a strategy guide (after beating the game of course
) and when I came across the place where you fight the shark, it even said to just shoot it a bunch (and noted that you should have enough ammo)... and I'm thinking "WTF? I figured out the thing you toss in the water and electrocute it with the first time I was there"
And lisa you don't even fight, you just run from soooo.....