Can I activate this card's [All Turns] effect and place 4 [Vemmon] at the bottom of their owners' decks to prevent it from leaving the battle area when this Digimon is affected by a <De-Digivolve> effect?
Show ruling
Official Ruling
No, you can't.<De-Digivolve> is not considered an effect where a Digimon would leave the battle area.
