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This round is very straightforward. Be careful about using the jump-attack as it can't be stopped and you'll end up in the water, so only go in the water when you have to. When you reach the end, fall into the water and break into the area with the door.

In the next area, head to the far right and grab the fire potion. Use it on the ice and swim to the right. When you surface hit the pot to the right first as it contains loot, and hitting the pot to the left will make it disappear.