Advanced format ruling
Ancient Forest
Card effect (current official text)When you activate this card, change any Defense Position monster(s) to face-up Attack Position. Flip Effects are not activated at this time. If a monster attacks, destroy it at the end of that turn's Battle Phase.
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.