Target 1 of your banished "Crystron" monsters; Special Summon it, and if you do, if your opponent controls any face-up monsters, change their DEF to 0.

During either player's turn, except the turn this card was sent to the Graveyard, when a card or effect is activated that targets a "Crystron" monster you control: You can banish this card from your Graveyard; negate that effect.