Arrow of Exchanging Fate

Touch a non-magical arrow and imbue it with magic, causing it to make the soft sound of a jingling bell until the start of the caster's next turn. The arrow disappears when it hits a creature as part of a ranged attack, appearing to absorb into their body, ending the sound. This creature takes no damage from the ranged attack and regains hit points equal to the caster's Spellcasting Ability Modifier. The caster's HP maximum is lowered to an amount equal to the amount that the arrow would have dealt if this spell hadn't been cast. They go back to their normal HP maximum at the end of a long rest. If the arrow hits the caster the spell ends immediately and the caster takes the damage they would have been dealt if the spell had never been cast.

At Higher Levels: At 5th level, the hit points regained by the target increases by 1d4. At 11th level, it increases by another 1d4 and the caster can make a constitution saving throw against their own Spellcasting DC. On a success, the necrotic damage is halved. At 17th level, the regained hit points increase by another 1d4 and the caster has advantage on the constitution saving throw.