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

Can my [Marcus Damon] Tamer, that gains +3000 DP and <Security Attack +1> from this card's <Your Turn> effect, attack as just a Tamer?
No. Tamers cannot attack, so a [Marcus Damon] Tamer in the battle area can't attack. However, if an effect such as the one on [BT12-092]/[Marcus Damon] causes it to be treated as a Digimon, then it is able to attack.
Ruled Mar 28, 2024
When an effect that targets Digimon with 3000 DP or less is activated, can a [Marcus Damon] that gains +3000 DP from this card's <Your Turn> effect be chosen as a target for that effect?
No, effects that target Digimon can't target a [Marcus Damon] that's just a Tamer in the battle area.
Ruled Mar 28, 2024
My [Marcus Damon] digivolved into a Digimon with a "you may digivolve as if your Tamer is a level 3 Digimon" effect. In such cases, what happens to the +3000 DP/<Security Attack +1> that [Marcus Damon] gained from this card's <Your Turn> effect?
This effect is not an effect with a set duration such as "for the turn," so the effect is lost unless the Digimon's name is still [Marcus Damon] after digivolving.
Ruled Mar 28, 2024
Is a [Marcus Damon] that gained +3000 DP by this card's <Your Turn> effect treated as a Tamer with 3000 DP?
No, Tamers can't have DP, so it's not treated as a Tamer with 3000 DP.
Ruled Mar 28, 2024
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