Harry Potter - Secrets of Hogwarts

Whenever you cast this spell on an active defensive spell within range that improves a creature’s AC or grants it temporary hit points, each creature affected by the targeted spell gains temporary hit points equal to twice your caster level + your spellcasting ability modifier. When the targeted spell ends or an affected creature is no longer affected by it, the creature loses any remaining temporary hit points from this spell. If you are maintaining concentration or dedication on a defensive spell, this spell can uniquely be cast on that active defensive spell without ending that spell or breaking your concentration or dedication.