The above image isn’t from the first boss battle in The Witcher 2. It’s just from the first one that made me mad.
There’s really no point telling you the backstory, which won’t matter to you unless you’re playing The Witcher 2. But the main point is that this guy is the same kind of guy as you. He has all your powers. Well, all the powers you’re supposed to get when you eventually level up, but you have to fight him before that happens. So he’s popping out all the spells, abilities, and inventory items that you didn’t get because you opting for other spells, abilities, and inventory items. Plus, he’s got way more hit points than you and he does way more damage than you do.
I don’t know how you’re actually supposed to get through the battle. For me, it was a matter of playing it over and over and over, giving up for the day, trying again the next day, Googling message board posts that were no help, watching YouTube videos that were equally unhelpful, and just plugging away some more. I finally beat him when he glitched and got stuck against a wall. It was at least 20 attempts.
It reminds me a bit of the Jedi Knight games. You’ve been running around totally being a badass Jedi, lightsaber and Force Powering your way through the game. Then you have to fight another Jedi who has all your powers and it’s no fair. I was supposed to be the big fish in the pond!