Megalith Portal (IGAS-EN057) [Ignition Assault]

The first time each Ritual Summoned monster would be destroyed by battle each turn, it is not destroyed. If a "Megalith" monster is Special Summoned (except during the Damage Step): You can target 1 Ritual Monster in your GY; add it to your hand. You can only use this effect of "Megalith Portal" once per turn.