2 official rulings from Bandai, last ruled Mar 28, 2024. Straight answers to how this card actually resolves.

I have 9 cards in my trash and a Digimon with this card as a digivolution card is deleted in battle. The deleted cards, including this one, are sent to my trash, and now I have over 10 cards in my trash. Does this card's <Retaliation> activate?
No. You lose this card's inherited effect when it is placed in the trash, so it can't activate.
Ruled Mar 28, 2024
I have 10 or more cards in my trash and a Digimon with this card as a digivolution card is deleted in battle. Before this card's effect has a chance to activate, another effect activates and reduces the number of cards in my trash to 9 or less. Does this card's <Retaliation> activate?
Yes, if you had 10 or more cards when it was deleted, you can activate <Retaliation>.
Ruled Mar 28, 2024
Got a line that uses Xiaomon? Map it in the builder and share it with a link.
Questions and answers are Bandai's official rulings, collected and translated by the DigimonCardGame Wiki community and reused here under CC BY-SA. Card names and card text are © their respective publishers; Combalo is not affiliated with Bandai.