2 official rulings from Bandai, last ruled Jan 10, 2025. Straight answers to how this card actually resolves.

My opponent has no Digimon with as much or more DP as this card in the battle area. I used this card to attack an opponent's Digimon, and the opponent's Digimon is deleted in the battle. Then, if an <On Deletion> effect on the deleted opponent's Digimon activates and my opponent now has a Digimon with as much or more DP as this Digimon, can I use the gained <Piercing> to perform a security check?
Yes, you can use <Piercing> to perform a security check. As soon as this card deletes an opponent's Digimon in battle, the <Piercing> gained from this card's <Your Turn> effect and the deleted Digimon's <On Deletion> effect will trigger simultaneously, then the turn player's <Piercing> will activate first. When <Piercing> activates, "perform check before End of Attack timing" processing will be pending, and the check will be performed immediately before the End of Attack timing, even if <Piercing> is lost after activation.
Ruled Jan 10, 2025
My opponent has no Digimon with as much or more DP as this card in the battle area. This card performs a security check, the <Security> effect on the 1st card checked activates, and my opponent now has a Digimon with as much or more DP as this card. Can I then use the <Security Attack +1> gained from this card's <Your Turn> effect to perform a 2nd security check?
No, a 2nd security check can't be performed using that <Security Attack +1>. The <Security Attack +1> gained from this card's <Your Turn> effect is lost as soon as your opponent has a Digimon with as much or more DP as this card, therefore you can't use the gained <Security Attack +1> to perform a security check.
Ruled Jan 10, 2025
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