Special Summon it to the field, and if you do, turn it into a non-Tuner, but banish it when it leaves the field
Dark Magic Mirror Force Normal Trap Card When an opponent's monster declares an attack, or an opponent's monster effect is activated that would destroy a monster(s) on the field, while a monster that mentions "Gold Sarcophagus of Light" is on the field: Destroy as many of your opponent's Attack Position monsters as possible, then, if you control "Dark Magician", inflict 500 damage to your opponent for each monster destroyed
Heatran takes 20 additional damage from Water-type attacks
A better alternative could be a card like Mystic Tomato, which can search out stronger monsters upon being destroyed, providing more versatility and value in various situations
They also share a hilarious New York Times article from 1999 with some warnings for young trading card investors