The leviathan in Dead Space has brought me to a complete stop in the game. I've tried killing that damn asshole more times than I can count, with each time taking roughly 15 minutes or more. It's ridiculous how difficult this boss is.
The problem is the lack of ammo mostly. Once I run out I just circle that area hoping to find something. Then I eventually get pounded by one of those tendrils and die.
My opinion of the game is still overwhelmingly positive, but this has really thrown a wet blanket on the experience. I've ignored just about every other game (including City Folk) because I want to make it through Dead Space.