Rulings
Q1: Can I use this card's End of Your Turn effect to give Piercing to 1 of my Digimon, but then choose to not attack with that Digimon?
No, you can't. The Digimon that was given Piercing by this effect must attack if possible.
Q2: I have 2 copies of this card in the battle area. At the end of my turn, I used the End of Your Turn effect on the 1st copy of this card to attack. Can I then use the End of Your Turn effect on the 2nd copy of this card to attack?
No, an attack using the 2nd effect isn't possible. A new attack declaration can't be made during an attack. In this case, the End of Your Turn effects on both copies of this card trigger simultaneously at the end of your turn, and you use the End of Your Turn effect on the 1st copy of this card to attack. The 2nd End of Your Turn effect can be activated before the counter timing, but because you can't declare another attack during an attack, you won't be able to attack using the 2nd effect, even if you activate it.
Data Sources
Owen Dreadnought BT21-081 R LIBERATOR [Start of Your Main Phase] If your opponent has a Digimon, gain 1 memory. [End of Your Turn] By suspending this Tamer, 1 of your Digimon with the [Reptile] or [Dragonkin] trait gains <Piercing> for the turn. Then, that Digimon attacks. --- [Security] Play this card without paying the cost.
Owen Dreadnought BT21-081 R LIBERATOR [Start of Your Main Phase] If your opponent has a Digimon, gain 1 memory. [End of Your Turn] By suspending this Tamer, 1 of your Digimon with the [Reptile] or [Dragonkin] trait gains <Piercing> for the turn. Then, that Digimon attacks. --- [Security] Play this card without paying the cost.
Owen Dreadnought BT21-081 R
LIBERATOR
{{StartYourMain|memory}}.
[End of Your Turn] By suspending this Tamer, 1 of your Digimon with the [Reptile] or [Dragonkin] trait gains <Piercing> for the turn. Then, that Digimon attacks.
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