Tengu format ruling
Core Blast
Card effect (current official text)You can only activate this card's effect while you control a face-up "Koa'ki Meiru" monster. Once per turn, during your Standby Phase, if your opponent controls more monsters than you do, you can destroy a number of cards your opponent controls so that your opponent will control the same number of cards as you control monsters.
Rulings
- This effect does not target.
- You can destroy any cards your opponent controls, not just monsters.
- If you do not control a face-up "Koa’ki Meiru" monster when the effect of "Core Blast" resolves, you can still destroy your opponent’s cards.
- You can activate the effect of "Core Blast" in the same Chain that you flip the card face-up.
Rulings data courtesy of Format Library — formatlibrary.com. Spotted an inaccuracy? Flag it in the Tengu forum — sourced change requests get reviewed.