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

Can I use this card and then place this card in digivolution cards without digivolving 1 of my Digimon without [X Antibody] in its digivolution cards?
No, you can't. If digivolution isn't performed using this card's effect, you can't place this card in digivolution cards.
Ruled Mar 28, 2024
If a Digimon has this card in its digivolution cards, does that mean that it isn't treated as "1 of your Digimon without [X Antibody] in its digivolution cards"?
That's correct. This card has a "Name: Also treated as [X Antibody]" rule, therefore a Digimon with this card in its digivolution cards isn't treated as "1 of your Digimon without [X Antibody] in its digivolution cards."
Ruled Mar 28, 2024
Does this card's inherited effect only activate if both [X Antibody] and a Digimon card are in the digivolution cards?
No, it activates even if only this card is in the digivolution cards.
Ruled Mar 28, 2024
If a Digimon with this card in its digivolution cards would be deleted other than by one of my effects, then an effect such as <Decoy> prevents it from being deleted, does this card's inherited effect activate?
Yes, it activates.
Ruled Mar 28, 2024
Got a line that uses X Antibody Proto Form? Map it in the builder and share it with a link.
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