Some spells and other effects require Concentration to remain active, as specified in their descriptions. If the effect’s creator loses Concentration, the effect ends. If the effect has a maximum duration, the effect’s description specifies how long the creator can concentrate on it: up to 1 minute, 1 hour, or some other duration. The creator can end Concentration at any time (no action required). The following factors break Concentration.
Another Concentration Effect. You lose Concentration on an effect the moment you start casting a spell that requires Concentration or activate another effect that requires Concentration.
Damage. If you take damage, you must succeed on a Constitution saving throw to maintain Concentration. The DC equals 10 or half the damage taken (round down), whichever number is higher, up to a maximum DC of 30.
Incapacitated or Dead. Your Concentration ends if you have the Incapacitated condition or you die.
SRD 5.2.1, p.179 · CC BY 4.0
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