beating OoA first will make OoS much easier and more fun overall because you get an extra heart container, you get the blue ring and you get the snowshoe ring (on the last dungeon you will thank me for it) If you play OoS first you get the red ring for OoA and it makes everything die, very quikly, veran dies before she can jump once in her turtle form if you have the red ring and master sword. The one that you want to be harder you should play first because you will have many advantages (secrets or not) in the other game

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i have FULLY completed and i mean fully completed Oot, Alttp, Oos, Ooa, La, Loz (1st quest), Mc, WW, MM, Aol
and i almost forgot FSA although it really isn't a Zelda game
pending: Loz (2nd quest)

Inuyasha to Kagome: "take it [clothing] off"

Favourite anime:
Naruto, Bleach, InuYasha, FMA, Love Hina, Eureka 7, Ai yori Aoshi +/- ~enishi~