FREEEEEEEEMAAAAAAAAAAAAN
From what I gathered, in this version of the game, you have to kill the Ichthyosaur and Gargantua before the Nihilanth will open up its head. That's why I took the time to kill them. You don't have to kill them in the PC version.
I remember my first time beating this guy...we doubled KOed each other. I'm not kidding, we killed each other at the same time. It was both funny and horrible.
