Held items

Depends on the Special Attacker - Pikachu for example does great with curse items on its thunder/thunder bolt move set because it can spread the curse effect to multiple enemy pokemon with its area of effect attacks, another good curse item user is Chadelure with its Overheat. Your typical mages like Gardevoir and Delphox probably still want to keep their Special attack and cooldown reduction items because their spell damage is more impactful and important than spreading anti-healing.