How Graves Work
On death, DKGrave inspects the actual drop list, chooses a safe nearby block and stores the items. The owner can collect by left-clicking, right-clicking or attempting to break the grave head. The plugin tries to move all stored stacks to the player's inventory; stacks that do not fit remain in the grave instead of being discarded.
The same grave can therefore be opened more than once until it is empty. Once all items are collected, the grave block, hologram and persistent record are removed. A normal player head without DKGrave's persistent identifier is never treated as a grave.