Mado's Curse

Mado's Curse is one of Servant Mado's signature moves. It increases physical damage dealt to the enemy, and also does a small amount of physical damage to them initially, usually around 90-150.

Visually, it appears to be a few Eldricahn runes floating around the target with Mado's soul cutting purple lightning, then a bolt of the soul cutting lightning strikes down at the target.