Once they receive the package, they will verify the cards that you have sent to make sure they are in the correct condition as you stated
Hence one can consider extending beyond the mainstream 40-card limit, but beware of hurting this decks' consistency
Standard foil cards remain the baseline across the set
Players coming in from other trading card games might forget that Magic: The Gathering has a whole second main phase after combat during which you can play sorceries and permanents, as well as activate all of those abilities that say "activate only as a sorcery." Even if you don't have a Wrath of God to wipe out your opponent's board post-attack, there are still a lot of things you can do, and the raid mechanic serves not only to remind you that there's a second main phase, but also encourages you to attack
Its impossible to predict where the metagame will end up, so I know my list wont be 100% correct by the time Eldritch Moon leaves Standard, but this should be a fun feature to show what cards I believe will have the greatest impact on Standard
Its very good, and its the kind of card where if you blink, youll be dead before you know it