Tengu format ruling
Megarock Dragon
Card effect (current official text)This card cannot be Normal Summoned or Set. This card cannot be Special Summoned except by removing from play a Rock-Type monster(s) in your Graveyard. The original ATK and DEF of this card become the number of Rock-Type monsters you removed from play when you Special Summoned this card x 700.
Rulings
- The only way you can Special Summon this card is via its own procedure. Even if it was initially summoned that way, you still can't summon it with card effects.
- If this card's effects become negated, or if it is flipped face-down, its ATK becomes 0.
Rulings data courtesy of Format Library — formatlibrary.com. Spotted an inaccuracy? Flag it in the Tengu forum — sourced change requests get reviewed.