For me, the hardest temple in MM would be the Great Bay Temple. Ugh, that temple was the first 3D water dungeon in the Zelda series that I came in contact with and I find it to be even more difficult than the OoT's water temple (I know shocking, isn't it? :O). What really got me in that dungeon was that you had to change the flow of the water in order to get into some of the rooms.
The hardest boss for me in MM? Well, I believe that would be Majora's Wrath. The first few incarnations of that boss wasn't as hard as it's last incarnation. Gah! I remember dying at that part of the battle at least once, maybe even two times. It wasn't until I finally realized that I could use my shield to get close enough to him to hit him (I had run out of arrows at this point... -.-). Needless to say, now that I know how to beat him, I don't find him that difficult now.
The hardest boss for me in MM? Well, I believe that would be Majora's Wrath. The first few incarnations of that boss wasn't as hard as it's last incarnation. Gah! I remember dying at that part of the battle at least once, maybe even two times. It wasn't until I finally realized that I could use my shield to get close enough to him to hit him (I had run out of arrows at this point... -.-). Needless to say, now that I know how to beat him, I don't find him that difficult now.
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