Arionpos, serpent of the ghoti

When you cast this spell, you may exile 1 fish creature with total mana value 6 or less from your library

If this creature was put into graveyard to cast another creature, you may target 1 fish creature in your graveyard: exile target creature, then you may search for a fish creature with equal or less mana value of the exiled creature by this ability, reveal it and put into your hand