I guess it depends on the sort of build you have... Here are some tips I use for him, but I've only killed him twice.suitepee7 said:ot: beating satan (and the whole oh sheol) in the binding of isaac. it is hard enough to get to, about 40 minutes (if your run goes lucky) and then you fight a stupidly hard boss, and if you die then its over, there goes 40 minutes.
still can't beat that asshole >_>
On his first form (The Fallen?) push a bomb at it when it splits into 2 for an easy hit and a good amount of damage.
In the second form, by sticking to the side of him he will only fire out the blood balls, which I think are easier to dodge than the lasers, but you need to switch sides quite often as he closes in towards you.
I don't really have anything for the third stage, just keep moving, but that's kind of obvious :/
I'm sure you will be able to find better tips if you want to search for them, but I found those things useful.
On a side note I always get Dr Fetus when I play as ???(The Dead baby), it makes me laugh and scream at the same time.
ot: Already mentioned but I vote for the Witcher 2 first boss fight, made me feel lame for looking at a video of how to do it, I got stumped at the end where you have to go up on some rubble to kill the damn thing.