just google it then pick the one on newgrounds step by step walkthrough with chest locations by screen. btw the one u missed is probuly the one under the big tree aross the river from where the weird guy is.
Too make the gnome riding the beast throw his spear every pass stand on the rock in the center (its kinda small and there is a rock lower to the left) and when he starts running at u after the 2-3 screen shake right before he comes onto the screen run downwards as much as you can he should throw every time
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