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

Does this card have inherited effects even though it's an Option card?
Yes. This card's <Main Timing> effect can place it in a Digimon’s digivolution cards, and it has inherited effects. As with Digi-Egg cards and Digimon cards, this card's inherited effects can activate while it's placed in a Digimon’s digivolution cards.
Ruled Mar 28, 2024
Can this card's inherited effect digivolve a Digimon that doesn't meet the digivolution requirements into a Digimon card with [X Antibody] in its traits in my hand?
No, you can’t ignore digivolution requirements when using this card's effect.
Ruled Mar 28, 2024
Can I activate an effect that reduces the digivolution cost when digivolving using this card's inherited effect?
Yes, as long as the activation conditions are met.
Ruled Mar 28, 2024
Can this card be trashed by effects on Digimon with this card in its digivolution cards?
No. Trashing by is also trashing by an effect.
Ruled Mar 28, 2024
What happens if this card becomes the top card after a Digimon with this card in its digivolution cards is affected by <De Digivolve>?
As with Digimon without DP, this card can't exist in the battle area as the top card, therefore it's trashed. This isn't considered deletion. If this card has other digivolution cards under it, they are also trashed.
Ruled Mar 28, 2024
What happens if a "trash the bottom 2 digivolution cards of your opponent's Digimon" effect activates on a Digimon with this card as its bottom digivolution card?
Effects can't trash this card, therefore only the digivolution card on top of this card is trashed.
Ruled Mar 28, 2024
There are 8 digivolution cards under [EX2-007]/[Mother D-Reaper], and this card is the bottom card. Does the "you may trash 7 or more digivolution cards from the bottom of 1 of your [EX2-007]/[Mother D-Reaper]s to set this Digimon's play cost to 0" effect activate when my [EX2-055]/[Reaper] is played?
It can activate in such cases if you declare to trash 8 cards and then trash 7 cards except for [BT9-109]/[X Antibody].
Ruled Mar 28, 2024
Got a line that uses X Antibody? 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.