5 official rulings from Bandai, last ruled Sep 13, 2024. Straight answers to how this card actually resolves.

Does this card’s <When Digivolving> effect activate when performing a non-DNA digivolution?
When performing a non-DNA digivolution, only the “Place 1 yellow or purple Digimon card from your trash on top of your security stack face down” part of the effect activates. The part of the effect that reads, “you may search your security stack for 1 level 5 or lower Digimon card and play it without paying its memory cost” only activates when DNA digivolving. “Then, shuffle your security stack” activates no matter what kind of digivolution you perform.
Ruled Mar 28, 2024
Does this card's <All Turns> effect also activate when the <Security> effect of one of my Security Digimon plays it into my battle area?
Yes, it does.
Ruled Mar 28, 2024
Does this card's <All Turns> effect activate when [BT1-089]/[Mimi Tachikawa]'s effect moves a Digimon from my breeding area to my battle area?
No, moving a Digimon from your breeding area doesn’t count as playing it, so the effect doesn’t activate.
Ruled Mar 28, 2024
My level 4 Digimon was played by an effect, then this card's <All Turns> effect and another effect triggered simultaneously. I activated the other effect, then the level of my Digimon that was played by an effect increased from 4 to 5. If I then activate this card's <All Turns> effect, what levels of Digimon can I delete?
Level 4 or lower. If the same reference to an "X" trigger condition being performed is made for an effect when it has a "when X" trigger condition, the state when the effect has triggered will be referenced. In this case, your Digimon was level 4 when this card's <All Turns> effect triggered, therefore you can delete a level 4 or lower Digimon.
Ruled Sep 13, 2024
My level 4 Digimon was played by an effect, then this card's <All Turns> effect and another effect triggered simultaneously. I activated the other effect, then my Digimon that was played by an effect was removed from the battle area. If I then activate this card's <All Turns> effect, can I delete an opponent's Digimon?
Yes, you can delete a Digimon. If the same reference to an "X" trigger condition being performed is made for an effect when it has a "when X" trigger condition, the state when the effect has triggered will be referenced. In this case, your Digimon was level 4 when this card's <All Turns> effect triggered, therefore you can delete a level 4 or lower Digimon.
Ruled Sep 13, 2024
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Questions and answers are Bandai's official rulings, collected and translated by the DigimonCardGame Wiki community and reused here under CC BY-SA. Card names and card text are © their respective publishers; Combalo is not affiliated with Bandai.