Skeldritch

Skeldritch is the fifth boss in Spirit Tracks. Its appearance is very similar to that of Stallord; it appears as a large skull with a spine that rises from the center of a large, ruinous room filled with sand, although it lacks arms and a ribcage, and it also sports a large, horned helmet. The skull is also more human-like than Stallord's beast-like skull.

Strategy
Skeldritch will fire large rocks at Link, at which point, he will need to use the Sand Wand to create walls of sand that will deflect the attacks. He can then push one of the rocks into a nearby catapult and fire it back to one of Skelditch's vertebrae to destroy it. However, the last three bones are protected by armor, and Link must get Skeldritch to face a different direction in order make his exposed point face a catapult and fire at the switch with an arrow while Skeldritch is in this position. When merely the head is left, it will float around the arena, and try to ram into Link. If surrounded by a wall of sand, Skeldritch will attempt to break out, allowing Link to attack the ruby-like weak point on the back of his skull.

Trivia

 * In the PAL version of Spirit Tracks, Skeldritch is named Capbone. The name most likely derives from the words cap and bone, as the boss sports a helmet (cap) and is skeletal in appearance (bone).
 * Skeldritch's name is derived from the words "skeleton" and "eldritch." "Eldritch" is a word meaning "unearthly," "alien," "supernatural," "weird," "spooky," or "eerie."
 * Skeldritch is one of the largest bosses Link has ever fought, including Cragma, Eox, Dark Dragon, Bongo Bongo, Molgera, Morpheel, and Stallord.
 * Despite the bony, skeleton-like appearance, there is no concrete evidence linking the boss to the famed Stal family of enemies, a clade that includes the Stalfos, Stalhound, Stalkin, and the Stalchildren, all of which exhibit skeleton-like physiques.