Midnight Masks

Other encounter sets in this scenario: Chilling Cold, Nightgaunts, Dark Cult, Locked Doors

My take on this encounter deck: This is a very small encounter deck that is of course meant to supplement the unique Cultist deck. Because of that, it doesn’t contain any real threats except for the Nightgaunts and Wizard of the Order. Instead it is focused on trying to stall the player’s progress by stopping them from investigating (Locked Door, Obscuring Fog), making them move around the map to deal with doom on enemies or straight up removing the clues that were already collected. It does this job very well.
Counter these: Unless playing with Returns To and thus adding the Masked Horrors treachery, there is no real standout treachery to save up a cancel for. Chilling Cold, On Wings of Darkness and False Leads are all worthwhile cancel targets if the player who drew the card can not expect to pass the relevant stat test.
My take on this encounter set: The Midnight Masks card set is special in that the scenario specific treacheries have been used like a normal encounter set in multiple other scenarios: Echoes of the Past, Phantom of Truth, Threads of Fate and In the Clutches of Chaos all use Hunting Shadow and False Lead. It’s easy to see why, as this role of attacking already collected clues makes sense to include in those scenarios and isn’t represented in any of the other core encounter sets. Those five cards should probably have been their own encounter set.

What it does: Hunting Shadow deals two damage to the investigator unless they are willing to spend a clue. That clue goes back to the pool and is lost completely. The card has Peril, so the decision has to be made by the player on their own.

My take: Simple but effective. As long as the health is not under pressure from elsewhere, the player can avoid losing a clue here most of the time. But especially when drawn multiple times, something encouraged by the small deck size in Midnight Masks, the damage can add up. Furthermore, most of the scenarios using Hunting Shadow also use other damage treacheries like Wings of Darkness from the Nightgaunts set or Grasping Hands from Ghouls to make the damage off of Hunting Shadow even more relevant.

Threat level: Low to Mid. Two points of testless damage can add up and losing clues can often be a setback equivalent to multiple actions

Dealing with it: In most cases, losing the clue is to be avoided. That means dealing with the damage, either by using assets that can soak it or simply having the health to spare by avoiding damage from other sources.

What it does: If the investigator has at least one clue, he needs to take an intellect test. For each point they failed by, they need to return one of their clues to their location. False Lead surges if the player has no clues to lose.

My take: The card has a fairly high ceiling, losing four clues to it would be really terrible. To prevent this, players are pushed by this card to spend their clues to advance the scenario goal. For Midnight Masks itself this means putting enemies from the Cultist deck into play.
In practice, failing the intellect check will usually result in about two actions, depending on the shroud value of the location. Not great, but also not too bad.

Threat level: Low to Mid. While the treachery itself doesn’t hit very hard, it’s mere presence in the deck forces players to spend their clues or risk losing them.

Dealing with it: There are many variables that depend on the current situation that determine how important passing that test is. An investigator with low intellect will have a harder time picking up the clues again, so for them boosting their skill value with card icons can be very worth it. The shroud value and any relevant restrictions and abilities on that location also are a significant factor.
As mentioned before, keep the impact of this treachery minimal by spending your clues on advancing the scenario when possible. Otherwise you risk losing a full turn or more to drawing an auto-fail and dropping four clues.

Return to the Midnight Masks

My take on the modified scenario: In addition to adding some more variety to the Cultist deck and the locations, the Return to The Night of the Zealot box also features a new treachery for use in this scenario.
More importantly, it switches the Dark Cult set for the Cult of the Devourer. This is a very significant upgrade to all of the cards from that set and the Disciple of the Devourer in particular plays right into the scenario with its ability to snatch up clues from players.
A great update on a scenario that was excellent to begin with.

What it does: Masked Horrors deals two points of horror to anyone holding two or more clues. If no horror was dealt this way, it will instead add a doom that can immediately advance the agenda.

My take: Nasty. The players are on a clock in the Midnight Masks, so adding more doom is absolutely something to avoid. Doing that requires to keep two clues around at all times, which slows players down as well and adds some pressure from the horror that is dealt in that case. At the same time, it empowers all the other cards in the deck that try to take clues away. Deciding on playing around this card is worth it or not is very difficult and may just not have a good answer at all.

Threat level: High to Very High. Even just playing around this card to stop it from becoming an Ancient Evils will severely impact the player’s progress and makes all of the other cards that steal, remove or drop clues more relevant.

Dealing with it: The impact this card has on almost half of the rest of the encounter deck when trying to avoid the doom makes it almost worth to just take it as an Ancient Evils and not get bogged down further. This is a priority card for which to save up a cancel like Ward of Protection or Test of Will.