Cartorhyn the Hidden Gem of the Seafront

You can discard this card; you can Normal Summon 1 EARTH or WATER monster during your Main Phase this turn, in addition to your Normal Summon/Set. (You can only gain this effect once per turn.) If you control an EARTH and WATER monster(s), while this card is in your GY: You can Special Summon this card, but banish it when it leaves the field. You can only use each effect of "Cartorhyn the Hidden Gem of the Seafront" once per turn.