If this Digimon is unsuspended, then it's suspended by an opponent's "Suspend 1 of your opponent's Digimon. That Digimon can't unsuspend during your opponent's next unsuspend phase" effect, are effects that prevent unsuspending during the unsuspend phase negated?
Yes. It's no longer affected by your opponent's effects as soon as it's suspended, so it can now unsuspend.
Mar. 28, 2024
Does this card's [All Turns] effect prevent [Security] effects on my opponent's Security Digimon from affecting this Digimon when it's suspended?
Yes, it isn't affected. [Security] effects on Security Digimon are treated as Digimon effects, so the "this Digimon isn't affected by the effects of your opponent's Digimon" effect prevents such effects from affecting this Digimon.
Mar. 28, 2024
