

Q1: Is the "while you have no face-up security cards" condition met when I have 0 cards in my security stack?
Yes, it's met.
Q2: What happens to cards placed face up in the security stack by effects?
They become face-up security cards that remain revealed. Other than rules that specify face-up security cards, the rules apply in the same manner as standard security cards.
Q3: What happens upon a security check for a security card that is placed face-up?
The check is performed with the card left revealed. Other than rules for cards left revealed, the rules apply in the same manner as standard security checks.
Q4: Does a card's Security effect trigger upon a security check with that card placed face-up?
Yes, it triggers.
Q5: What happens if I shuffle a security stack that includes security cards placed face-up?
Any face-up cards are placed face down, then you shuffle the cards. After shuffling, all cards are left face-down.
Cyberspace EDEN BT22-100 C
CS
While you have no face-up security cards, you can ignore this card's color requirements.
{Security} [All Turns] All of your Digimon with the [CS] trait get +2000 DP.
[Main] Add your bottom security card to the hand. Then, place this card face up as the bottom security card.
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[Security] You may play 1 play cost 5 or lower card with the [CS] trait from your hand without paying the cost.Cyberspace EDEN BT22-100 C
CS
While you have no face-up security cards, you can ignore this card's color requirements.
{Security} [All Turns] All of your Digimon with the [CS] trait get +2000 DP.
[Main] Add your bottom security card to the hand. Then, place this card face up as the bottom security card.
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[Security] You may play 1 play cost 5 or lower card with the [CS] trait from your hand without paying the cost.Cyberspace EDEN BT22-100 C CS While you have no face-up security cards, you can ignore this card's color requirements. (Security) [All Turns] All of your Digimon with the [CS] trait get +2000 DP. [Main] Add your bottom security card to the hand. Then, place this card face up as the bottom security card. --- [Security] You may play 1 play cost 5 or lower card with the [CS] trait from your hand without paying the cost.
電脳空間EDEN BT22-100 C
CS
自分の表向きのセキュリティがない間、このカードは色条件を無視できる。
{セキュリティ}【お互いのターン】特徴に「CS」を持つ自分のデジモン全てをDP+2000。
【メイン】自分のセキュリティを下から1枚手札に加える。その後、このカードをセキュリティの下に表向きで置く。
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【セキュリティ】自分の手札から、特徴に「CS」を持つ登場コスト5以下のカード1枚をコストを支払わずに登場できる。