2 official rulings from Bandai, last ruled Apr 4, 2025. Straight answers to how this card actually resolves.

What does a "your opponent can't reduce digivolution costs" effect do, exactly?
This effect prevents digivolution costs from being reduced when the costs are to be paid. This effect affects the opponent player.
Ruled Apr 4, 2025
Can my opponent digivolve a card using a "digivolve without paying the cost" effect while a "your opponent can't reduce digivolution costs" effect is activated?
Yes, it can be digivolved. "Digivolve without paying the cost" effects aren't effects that reduce the digivolution cost.
Ruled Apr 4, 2025
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