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

How does this card’s effect work if it activates when I have 0 cards in my security stack?
You can't add a card to the hand because you have 0 cards in your security stack, but you may perform "place 1 card with [Sukamon] from your hand on top of your security stack."
Ruled Mar 28, 2024
When I use this card's <On Play> effect to add 1 card from my security stack to the hand, do I have to reveal the added card to my opponent?
No, there are no requirements for the card you add to your hand with this effect, so you don't have to reveal it to your opponent.
Ruled Mar 28, 2024
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