Wrenn's Disseminating Martyrdom

You touch one willing creature, for the duration the creature is surrounded in a translucent aura and has resistance to all damage except psychic damage. Each time the creature takes non-psychic damage, record the total amount of damage dealt after the resistance calculation. The spell ends under any and all of the following conditions:

• If you or the creature affected by this spell becomes incapacitated, drops to 0 hit points, or dies outright.
• If you fail a concentration check as a result of taking damage.
• If you cast another spell that requires concentration.
• If you end your concentration on the spell (no action required and this does not have to be during your turn).

When the spell ends, each creature in a 20-foot-radius sphere must make Constitution saving throw. On a failed save, a creature takes force damage equal to the total damage dealt to the creature targeted by the spell and is knocked prone. On a successful save, a creature takes force damage equal to half the damage dealt to the creature affected by the spell and is not knocked prone.