The Secret Shrine is one of my favorite places, if that's what you're referring to. It's behind the waterfall which is one of the two water sources for the Southern Swamp (the other being Woodfall). You need the light arrow to enter, and there you can have a rematch with one of the minibosses from each temple. I won't spoil it for you by telling you who you fight, but from the doors are ordered by temple from left to right. You get a great prize afterward, and can fight them again every time you go back in time!

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Belief or disbelief rests with you. To die without leaving a corpse... that is the way of us Garo
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