Advanced format ruling
Swallow Flip
Card effect (current official text)Negate the activation of an Effect Monster's effect that activates when a monster is Special Summoned (including itself), and destroy it.
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.