I really admire how Capcom kind of defied all the usual things that you expect to see in a game, even a Resident Evil game by how they did a lot of what is in this game. This is part of the reason why I have really enjoyed playing it thus far.
Even though it kind of ticked me off at first, the innovative bosses of this game are like no others I have ever seen. The first boss is a tough fight because of the fact that he is only vulnerable during certain portions of the fight and they are not evident when that is and the same is true of the 2nd boss, but they do it in such a cool manner in that there is no real "arena" in which you are fighting the boss.
The second boss is Marguerite Baker, who is the mother of the really strange family occupying the areas that you find yourself in.
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In most games and even almost all Resident Evil situations, the boss fights consist of you walking into an area and then being shut in and forced to fight a boss in a particular fashion. The elements of dodging and what not are defined by that particular room, but with Marguerite, you are running all over a house with her kind of occasionally stalking you. She isn't relentless in her pursuit, and you can actually leave the arena and exit the fight if you so wish.
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Her attacks consist of throwing a bunch of insects at you and these are mostly throwaway enemies that do very little damage. The flamethrower comes in very handy here because although they don't do much damage, there isn't much other way to kill them since individual bullets are too small and the bugs are too many. I suppose you could throw away all your handgun ammo in an ill attempt at getting them.
Then every once and a while Marguerite stands in front of you and this is when you should probably switch over to something with a bit more firepower than the flamethrower, which isn't very effective at causing a lot of damage to one target. I haven't found it to be very useful in any other situation than with the bugs, actually.
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I thought it was really innovative for them to do a boss like this and honestly, this portion of the game is much easier than the one that you just left in the main house. It can be a nice break when a game does this to you because at least in my world, I found the first portion of the game to be almost a bit too difficult and this is why this is actually my 2nd time playing this game as I gave up the first time through when I played the game years ago.
The other bosses and sub-bosses that I have encountered have been pretty great in this game as well but I got to hand it to them for this particular fight. It is one of the best that I have ever seen in any game and a part of why I feel that way is probably because of the fact that it wasn't overwhelming like the first one was.
I highly recommend that anyone play RE: Biohazard. It has been one of my favorite Resident Evil experiences in the entire franchise's history.