Well, for me, I have the ability of the internet but I don't want to use it to find out what to do.

It's Dark Sector. I'm at this boss battle in a room that's filled about knee-deep with water and there's an invisible guy that is supposed to be defeated. I've tried just kicking him up and down the court but he won't die. (I've shot and punched him until I had no ammo left) I'm supposing there's some sort of environment thing to kill this guy but the room is so dark I can't even seen anything. Well, that's a lie, there is an environment thing where I introduce electricity in the water but that doesn't kill him ( I will direct your attention to how many times I've shot and punched this guy)

I just don't know what to do so I kind of quit that game.

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