They appear in "Sons of Mars." They are the older brothers of Magic Man. The four are often evoked as religious entities in the Land of Ooo, as Jake is shown to believe in "Glob World," and Finn at one point speculates Candy Kingdom people worship Glob in church.
Grob Gob Glob Grod is a roughly humanoid shaped being. They have four faces, one on each side of their head. The faces can sometimes all talk at once. They are also bald due to Magic Man casting a spell on them. Their head appears to be floating and not actually attached to their body. The red, jewel shaped part on their head is not part of their body, but a piece of headgear that conceals the baldness caused by Magic Man. The shape of their eyes vary from having dots for eyes to having fully drawn eyes during close ups. They have a sword that has a white spiky core that emanates a blue aura. [Source: wikia]
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