Apollomon

Q:In a state where my opponent had no Digimon, I used this Digimon with to attack, [BT3-036 Ankylomon] was flipped over for the 1st security check, and the [Security] effect played it as an opponent's Digimon at the end of the battle. When the 2nd security check is performed, can this card's [Your Turn] effect delete my opponent’s [BT3-036 Ankylomon]?

A:No, it can't. This card's [Your Turn] effect triggers "when a card is removed from your opponent's security stack," therefore it will trigger/activate when the 1st security check is performed, even if there are no targets. Because it's a [Once Per Turn] effect, it can't trigger when the 2nd security check is performed.