The Titans are the overarching antagonists of Deltarune. They are immensely powerful beings of pure destruction birthed when Dark Fountains become too strong, and are thus the harbingers of a prophesied apocalypse known as the Roaring. Titans are colossal, vaguely humanoid entities composed entirely of darkness, and their appearances vary greatly.

A Titan is the physical manifestation of the fear of the dark, the bump in the night, and the shadow of the backside of one's mind. It has no personality or cognition to speak of; it cannot be reasoned with, nor can it understand the concept of mercy. Titans exist solely to cause indiscriminate destruction to the world around them, and can create Titan Spawn to assist it in this goal. They are not above cannibalism, as when wounded they freely consume these Titan Spawn in order to heal. Per the Legend of Delta Rune, if the Titans are unleashed upon the world, the Earth itself will be shrouded in dark and die, all Darkners will petrify one by one, and Lightners will be forced to fight for survival in an eternal night. As Titans are in essence a Fountain given life, they can be killed by sealing the Fountain within it using the power of a human SOUL.