i think you can get that chest after activating all the stones (activate them with the spell) there are five stones in the forest: the one where you appear first, the second is very close on the second map, to the right. third in the next map you can go up on the left side, where the owls are, fourth after crossing the bridge, final one is on the big waterfall map, at the end of the path to the left. when you activate them all, the screen will shake and you will be able to continue with the path to the right side of the big waterfall
I am trapped here.