I actually found
AoL easy, although I have played through it a few times and know all the secrets.
I can't single out one game as the hardest, but I do thinl there are certain factors/sections of certain games that make them harder than others:
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LoZ for the navigation (finding your way around and actually finding where everything is and where you need to go next), although this doesn't apply to me since I cheat and use a map

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AoL is hard until you get past Death Mountain (which is fairly early in the game).
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ALttP is one of those 'hard the first time you play it' games
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OoT MQ is difficult because it is meant to be, so it is. Don't argue.
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MM I'd say has the hardest bosses,Gyorg (spl?) in particular.
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OoA I always find hard because of the blasted Goron dance.
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TWW, the triforce quest can be a stumbling block
-TRR can be difficult if you mess up on the negotiations, which results in you not having enough rupees to advance in the game, meaning it is then difficult (and dull) to collect the rupees you need to continue.
Surely however, the hardest game has to be
FS (suprisingly, not on the poll), since it is damn near impossible to find anyone to play with

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