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

This card doesn't have a level. Can I still digivolve into it and into other cards?
No. Cards that don't have levels can't be digivolved from, and you can't digivolve into this card. (Other than through special digivolutions.)
Ruled Mar 28, 2024
If this card's effect plays a Digimon, is it treated as a Security Digimon even in my battle area?
No, it's treated as a normal Digimon once it comes into play.
Ruled Mar 28, 2024
An opponent’s Digimon with attacks me directly, and this card is flipped over during the first security check and played in my battle area by its <Security> effect. If I have a [Mother D-Reaper] with 6 or more digivolution cards in play, can this card's <Opp Turn> effect prevent my opponent's second security check?
Yes. This card’s <Opp Turn> effect gives your opponent’s attacking Digimon before the second security check, so the second security check does not occur, and the attack ends.
Ruled Mar 28, 2024
Are Digimons played by the effect of this card treated as Security Digimon in the Battle Area?
No. From the time it plays by this effect, it is treated as a normal Digimon.
≪An opponent's Digimon with "Security Attack +1" attacked a player, and this card was turned over on the first check and played in the Battle Area under the [Security] effect. If there is my "Mother De Reaper" with 6 or more digivolution cards, can this card's [Opponent's Turn] effect prevent the opponent's second check?
Yes, it activates ≪Security Attack-1≫ on the attacking opponent's Digimon by this card's [Opponent's Turn] effect before the second check, so the second check is not performed and the attack is over.
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