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

If my opponent has no Digimon or Tamers, does that mean that I can't activate this card's <Main Timing> effect?
No, the effect still activates even when your opponent has no Digimon or Tamers.
Ruled Mar 28, 2024
Does "you may play 1 Tamer card with the [Night Claw]/[Light Fang] from your hand without paying the cost" in this card's <Main Timing> effect activate when my opponent doesn't have any Digimon or Tamers?
Yes, it activates.
Ruled Mar 28, 2024
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