Entering the Lakebed/water temple to get the last fused shadow, Link goes through the temple highering the water level and using water bombs and iron boots to open up new areas of the temple, the mini boss is a giant frog that spits out little fish and it's weskness is it's tougue, once defeated the Clawshot is aquired and used to assess the rest of the temple and to get assess to the boss key, the boss door is open, the Twilit aquatic Morpheel is defeated and the last piece of the fused shadow is adquired, they return to the cave of the Light spirit but when there Zant appears and attacks them turning Link back into a Wolf and blasts Midna with the Light spirit weakening her, the light spirit tells Link to head to see Zelda who will be able to help them
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https://www.youtube.com/watch?v=0weSe1hJc7s