Tengu format ruling
Blasting the Ruins
Card effect (current official text)You can only activate this card if there are 30 or more cards in your Graveyard. Inflict 3000 points of damage to your opponent's Life Points.
Rulings
- Even if you activate Blasting the Ruins and an effect is chained that reduces your GY to less than 30 cards, Blasting the Ruins still resolves because the condition was correct at the time of activation.
Rulings data courtesy of Format Library — formatlibrary.com. Spotted an inaccuracy? Flag it in the Tengu forum — sourced change requests get reviewed.