One od the worst drsigned cards in the game. Treachery cards that gice you no recourse to deal with them are a design flaw. The other issue is that for some xharacters this us trivial, while it is an almost guaranteed defeat for others.
Revelation - Put Beyond the Veil into play in your threat area if there is no copy of Beyond the Veil in your threat area.
Forced - If your deck has no cards in it: Take 10 damage and discard Beyond the Veil.
So here's my game state; I have Beyond the Veil in my threat area. One card left in my deck. Deny Existence in my hand (saving it for this exact treachery). I draw a card in upkeep, so Beyond the Veil triggers immediately and I use Deny Existence to prevent the 10 damage. Phew.
Unfortunately, your deck will only cycle when you would draw a card from an empty deck. So at this point, I still have an empty deck.
So what happens in the following mythos phase? I draw another Beyond the Veil, it goes into my threat area and immediately triggers. ...But wait! I have a Ward of Protection. PHEW!
But unfortunately Ward of Protection only cancels the revelation effect, so the "Surge" keyword still applies. Oh well, I can handle the subsequent surge card, I'm sure...
Beyond the Veil AGAIN! Are you kidding me?! Instant 10 damage, because at this point my deck is still empty. Never has Arkham Horror kicked me in the balls as hard as this. I took all the mitigation that could be reasonably expected for this card, and still I couldn't survive it. Not a particularly fun card to play around, but it sure is a memorable one.
This seems to be a contentious card, but in my opinion the worst part about the card is that it simply isn't fun or interesting. Many of the card milling mechanics in Dunwich don't have significant counterplay and it's easy to draw this at 10 cards left in your deck and just eat shit. Every other strong encounter card has something you can do to mitigate its effects, like passing a skill check. This is just really boring and doesn't make me excited to play Arkham Horror.
This card is a perfect example of how a treachery can shape the entire campaign. Dunwich has many cards that force you to discard undrawn cards, and although this can normally be bad enough (especially if it pushes cards you need into the discard pile) this card makes it a punishing, deadly mechanic if not built for.
Anyone playing Dunwich needs to build their deck with this card specifically in mind. There are several counter options for it, though some investigators really have no counter and should not be picked for Dunwich because of that.
For All -Consider resigning if running low and this is up. It is better to fail the scenario than take trauma, most times. This card gives you plenty of warning that it is going to kill you.
Survivor (can deal with this card) -Devil's luck: Straight out cancels the card if you can't counter it by other means. -Alter Fate: Get rid of the card from yours/an investigator's play area.
Rogue (will probably die from it) -No easy counter. Either tank it, run versatile with Deny Existence (keep in mind the extra cards you pick for versatile should have draw on them or you're going to run into deck dilution easily), or dump points into Cheat Death.
Guardian (will probably eat this but be fine) -No easy counter, but can stack a ton of mitigation to take the hit (I've had worse, just straight out tanking it, etc). Also guardians tend to have slower draw and even with the forced discards the event probably won't trigger.
Seeker (no direct counter but can probably cancel this) -usually very squishy and can't survive the hit once it goes off and also cycle their deck fairly rapidly. They are definitely at a higher risk from this card. However with abilities like Forewarning they can cancel it. Many of them also have access to the mystic card pool, in which case Deny existence or Quantum Flux can help tremendously.
Mystic (makes this card their bitch) -Having a high amount of cancels, deny existence (especially level 5), slow draw and quantum flux, this class is not in the least bit concerned by this card.
TLDR If your character can pull from the level 1 survivor pool or any cards from the mystic pool, they will likely be just fine. If they cannot, consider versatile for deny existence.