Grave Marker is a Positive type Psych and is only found on four pins. To use it, Slash vertically down on an enemy and Neku will teleport above it and attack with a downward stab. These pins range from 0s to 3.0s to Boot and 8.0s to 9.0s to Reboot. Grave Marker pins don't require as much attention as other pins and are good for when you need to focus on the top screen more than the bottom.
Grave Marker Pins are: