Phosphorage the Elemental Lord

Cannot be Normal Summoned/Set. Must be Special Summoned (from your hand) by having exactly 5 LIGHT monsters in your GY. When this card is Special Summoned: You can destroy all monsters your opponent controls. You can only use this effect of "Phosphorage the Elemental Lord" once per turn. If this face-up card leaves the field, skip the Battle Phase of your next turn.