Singularity of the Astral Plane (5e Equipment)
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Wondrous item, artifact (requires attunement)
Years ago, a champion of light, whose name lost itself with passing eons, spent extensive time meditating in the astral plane. After uncountable years, he managed to grab an understanding of this plane, used that peculiar knowledge to gather and solidify materia of it, then absorbed it into itself becoming first wielder of Singularity of the Astral Plane.
One with the body. After attunement to this artifact is complete, item incorporates itself into the user, and cannot be forcibly taken from him. When ending attunement user's body takes great strain, reducing Strength, Dexterity and Constitution to 2 each, with each passing day spent resting regaining 1 ability score up to their previous values.
Strength of the Astral Plane. Your body gains the strength of the astral plane. You gain + 2 to your AC, and you add +3 to attack and damage rolls you make with your unarmed strikes. Additionally, your unarmed strikes count as magical for overcoming damage resistances and immunities.
Connection of the Astral Plane. You can cast plane shift spell on yourself with these changes: you can cast it without components, you can take up to 20 willing creatures with you, you can target only the astral plane, spell save DC is equal to 8 + your proficiency modifier + your Wisdom modifier, on failed save creature is forcibly taken with you, unable to leave against your will by any magical means until you are incapacitated or you die, or through natural rifts in space. When you use this property you cannot do so until you take a long rest.
Will of the Astral Plane. While in the astral plane you know exact locations of beings in 5000-mile radius, both alive or dead, as well as portals to other planes of existence. You can differentiate them based on their colour but you do not know the final locations they lead to. In addition, you regain 10 hit points when you start your round in the astral plane. This effect is greatly reduced in other places, regaining only 1 hit point instead.
Indestructibility of the Astral Plane. When you die attuned to this item your body crumbles to dust, and your soul travels to astral plane, unable to resurrect yourself or leave on your own. Normal means of bringing dead back still apply to you, provided they recreate your body. While dead your soul keeps all your in-game statistics and abilities, you gain immunity to poison and radiant damage, and become immune to all negative conditions. If you end your attunement to artifact your soul leaves to afterlife, leaving item behind. if you die while in this state, your soul is forever destroyed and artifact appears in space you occupied.
Curse. While attuned to this item you are unaffected by all spells and effects that can transport you to other planes of existence other than the astral plane. You can travel to other planes only through the astral plane.
Destroying the Singularity of the Astral Plane. The unbelievable power of this artifact comes from gigantic bodies of ancient dead gods scattered across the astral plane. If those bodies were to be destroyed, gods brought back to life or plane left otherwise empty the artifact would lose its magical properties and disperse into nothingness alongside the whole plane, never to be seen again. Also, the first wielder of the artifact, or his soul if he has already died, know a secret way to unmake the artifact. If he is willing to share his knowledge, champion of light tells that when not attuned to anyone the artifact could be struck with enough power to crumble to dust, forever destroyed, but only when on the astral plane. In any other place this item is considered indestructible.