Let me tell you the story of a king.” “The inner sea of the planet. The platform of the watchtower. From the edge of paradise, you shall hear my words. Your story shall be full of blessings. ━Let only those without sin pass." "Garden of Avalon"!
Herald of Infinity: Merlin, being one of the Heralds of Infinity, possess the power to use any and all magic, mystiscm and virtually any spell in existence. However, Merlin is among the most powerful of maguc-users known anywhere in existence, due to his vast intellet on the subjects of the arcane, he is able to use Herald of Infinity in a unique fashion to the others. Merlin is able to alter virtually anything, and manipulate virtually anything with his level of skill being transcendent.
Garden of Avalon: One of Merlin's most powerful spells of spatial manipulationg and reality warping. By chanting a incantation, Merlin alters his surrounds, and the radius of space and reality to form the Garden of Avalon. The Garden of Avalon is a prison for Merlin when he entered the Stonehenge but was imprisoned. It is said he is actually still imprisoned there to never ever die for all eternity. As such, the real Merlin is still imprisoned, and he has send them there as well. Thus, those caught in this spell, is to for eternity be sealed within the Tower of Avalon.
Clairvoyance: Merlin is able to foretell into the future, and able to make prophecies, such as the story of the Sword in the Stone, and the hardships of King Arthur.
Meta Reality Manifestation: Merlin is able to "manifes" into the realit on the borders of existence. Using his spell allows him "return to the world and beyond" and interact with the physical and the spiritual/mystical/magical environments of the planes of existence. However, he stil forever sealed in the Tower, and the manifestation can be destroyed to which it will take some time before Merlin can cast it again.
True Immortality: As long eternally stays within the Tower of Avalon with the garden, Merlin is eternally out of the reach of death, and utterly transcended death in all aspects and concept. No matter who, no matter what or it enters the chambers of the tower, they will never kill Merlin even with near-limitless power. He is to never die, and shall never for all eternity. Despite this, this is on the border of being a curse, then a gift seeing Merlin remains eternally trapped in the Tower.