Antimagic (5e Variant Rule)
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The fibers of the universe are harnessed by magic - users. Whether to create fireballs or summon the undead, magic will almost certainly be harnessed in one way or another in a game of D&D. However, when this essential element is not present, magic spells cannot be cast and magical items lose their flair. When a spell is cast that creates antimagic fields, magic, consequentially cannot be used there. Magical items will no longer retain their properties upon entering an antimagic field, and magically sustained creatures such as golems or other animated objects will immediately, upon entering an antimagic field, disperse and become inanimate and will require another spell to be reanimated, or else they will sit there motionless. If a magically sustained creature is stopped in this way, when fifteen minutes after the antimagic field has dispersed, and the creature has not been placed in another antimagic field, it will become sterile and cannot become reanimated. However, if the creature is still in an antimagic field after its original animation spell was dispersed, it will remain able to be reanimated as long as the creature is moved outside of the antimagic field before the spell is recast.