You can discard 4 other ""Mermail"" monsters to the Graveyard; Special Summon this card from your hand. When you do: Target cards your opponent controls, up to the number of ""Mermail"" monsters in your Graveyard (if possible); this card gains 500 ATK, and if it does, destroy thos targets (if any). You can Tribute 1 other face-up Attack Position ""Mermail"" monster; this card gains the following effect this turn. // * At the start of the Damage Step, if this card battles a Defense Position monster. Destroy that monster.