Temple of Null (5e Equipment)
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Wondrous item, artifact (requires attunement by a worshiper of Aakronus)
An ancient relic said to be wielded by a high cleric of Aakronus during his conquest of the realms, this ancient relic disables all magical forces near it, creating a field of grey light. Before it has been activated, it resembles a 2 inch by 4-inch block of grey crystalline material.
Null Zone. When activated, an antimagic field expands out from the block in the shape of a 300-foot pyramid. Any constructs or undead of CR 10 or lower are instantly destroyed. The zone remains active as long as the attuned creature maintains concentration. While the temple is activated, it behaves like a holy place to Aakronus. Clerics of Aakronus do not need a holy symbol to cast spells.
Destroying the Temple of Null. If the one attuned to the temple is killed, the temple expands and contracts rapidly before collapsing in on itself, creating a 200-foot sphere of energy, dealing 5d20 necrotic damage and 5d20 radiant damage to any creature caught in its blast.