![[TDIL] Block Dragon Empty](https://2img.net/i/empty.gif)
Block Dragon
![[TDIL] Block Dragon Latest?cb=20160406084549](http://vignette1.wikia.nocookie.net/yugioh/images/9/98/BlockDragon-TDIL-JP-OP.png/revision/latest?cb=20160406084549)
Cannot be Normal Summoned/Set. Must be Special Summoned (from your hand or Graveyard) by banishing 3 EARTH monsters from your hand and/or Graveyard, and cannot be Special Summoned by other ways. Rock-Type monsters you control cannot be destroyed, except by battle. If this card is sent from the field to the Graveyard: You can add up to 3 Rock-Type monsters from your Deck to your hand, whose total Levels equal 8. You can only use this effect of "Block Dragon" once per turn.
Another cool friend for Rock-types like Giant Sentry of Stone.
I colored this special PSCT "Rock-Type monsters you control cannot be destroyed, except by battle" because most of you are asking why those words, and not "By Card Effects".
It's Simple, this way you protect your Koa'ki Meirus from their own Maintenance Cost which IS NOT an effect, and cannot be negated by generic stuff like Skill Drain and Company. So with this you can avoid to pay the Maintenance Cost and they will still survive. (Like with Diamond Core)