Advanced 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.
Current rulings for this card are maintained by Konami.
Rulings data courtesy of Format Library — formatlibrary.com. Spotted an inaccuracy? Flag it in the Advanced forum — sourced change requests get reviewed.