This is the easiest of the crystal hearts to collect.
Starting from Section Two of Chapter Four, grab onto the side of the moving block and guide it up through the center of the room, then guide it right to jump and dash through the ledge overhead to exit right. Get in the water and dive under the wall to reveal a secret area. Bash through the wall and exit right into the next zone, which houses the crystal heart.
Jump on top of the white block and hold
for a few seconds to end up behind the block and in the background. Now climb the background up to the very top to find the Crystal Heart simply dazzling in the light. Dash into it and enjoy your achievement.
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