This is a niche card that excels in or even trivializes some scenarios but most of the time isn't very useful. Do you need to clear a ridiculous amount of clues from one location? Is the enemy's strength tied to the location's shroud? Congratulations, you've just won the scenario.

The rest of the time, it let's a Guardian help a little with clues.

This card.

Holy moly. Golly gee. Horsefeathers. Applesauce. Bushwa. Hooey. Swell.
...F*ck.

First just some quick analysis on the card itself:

• It's dirt cheap to play. Run it with Robes of Endless Night and it's free.
• It's a Parley action. Since those are few and far between, here's your obligatory reminder that taking one does not provoke opportunity attacks.
• Option 1 gives you a testless clue and a testless evade at the cost of placing a doom and not being able to damage the enemy that round. That last part kinda bites, but it's good value, especially if played during the "witching hour", moreso on an enemy you can just sweep under the rug and move away from.
• With option 2, the resource cost of the spell is, at minimum, refunded right back to you. Nice! Any doom after the first is profit, which means this card can turn pressure into opportunity. Mysterious Chanting is a card that often translates to "kill this enemy now or lose", but if you've got String of Curses in hand, now there's a nice bounty to collect on that high value target, and it's a guaranteed kill.
• Note as well that option 1 only precludes damaging the enemy. You can still defeat it if you have a way to do that without dealing damage, like, say, playing String of Curses again. More on that later. (Other cards can do this too, and Waylay could be a decent combo. Or leave it to your friend playing Kymani Jones if they don't have VP.)
• The testlessness of both options makes this card worthy of consideration in Expert mode. I have no experience there personally, but going off the theory of wanting to touch the expert chaos bag as little as possible, this seems a decent choice.

Focusing on option 2, this seems like great tech for any scenario that uses the Dark Cult encounter set (quick tip: to date, you'll see it at least once in all but one campaign) to have a way to quickly deal with spiking doom placements. Many campaigns also have their own encounter sets with similar themes of cultists or other doom-oriented enemies (for brevity let's call them "doomers"), often featuring treacheries that place even more doom on enemies. If you've played Midnight Masks, Echoes of the Past, or Threads of Fate, you can probably guess what the peak performance of this card might look like.

Many doomers are weak, like your standard Acolyte, where having a value answer is nice but might be overkill when a simple Fight action would suffice (unless there's profit to be gained). But other doomers can be particularly nasty, and having a way to defeat them automatically in a single action might be just what the doctor ordered. You'll be surprised what you can cuss out, even in the furthest reaches of time and space.

This all comes with the solemn acknowledgment that as an event card, you're limited in the number of times you can actually play it. If you, like me, would like a way to play String of Curses more than once or twice in a game, you've got a few combos to consider:

• Dayana Esperence can cuss on tap, until she runs out of secrets. If you have a way to recharge her, and perhaps also a way to ready her, she's an unstoppable cultist cussing machine.
• If you're leaning into other doom tech, De Vermis Mysteriis allows you to cuss one last time after discarding.
• Recursion options in-faction include Prescient and Quantum Flux. Out-of-faction options include Scrounge for Supplies, Shrine of the Moirai, and I guess also The Council's Coffer.
• The new upgraded Uncage the Soul also allows you to play it from discard, but it will provoke opportunity attacks and the discount is mostly wasted.
• You can use Double, Double and one-two cuss a single target--evade and defeat an enemy AND discover a clue for 1 resource and 1 action! This sounds like the coolest combo to me, but outside of Versatile, the only investigators who can pull this off are Sefina Rousseau and Jenny Barnes.

...and so's your old man!

This is the only way to get back Becky once it is in your discard pile for Tommy Muldoon if it got accidentally taken away from you...

One copy of Salvage and 1-2 of Resourceful and Becky is safe from anything that doesn't take it out of the game :)

EDIT : NOPE, I'm an idiot that can't read a card for years, see the comments ;)

In my opinion the best Dilemma in The Scarlet Keys.
For 1xp, it's basically a 0-cost event that makes you draw 3 (you want the second option most of the time).

The downside is obviously that you cannot precisely control when At a Crossroads will trigger BUT :

• Most of the time you can spare an action for this.
• Don't forget you don't lose 1 action "immediately" but on your next turn so you can plan accordingly. And it will never destroy what you were planning to do this turn if you drew it during your turn (thus not during the upkeep phase).
• Katja Eastbank will help you with the "draw-timing" if it is that big of a problem for you.
• You always have the first option if you need a burst of action right now and/or you already have a lot of cards in hand.

Overall a really good card. Just be careful if your friends at the table also play some Dilemmas though ! :)

At level 0

This card is great right from the bat at level 0. It's basically 1 action for 1 card in your deck and 1 resource. You will have the opportunity to play both copies almost every game as most scenario has at least 2 agendas and 2 acts ! And if it is not the case, Rogues tend to oversucceed anyway... To trigger this "play condition", you can play Winifred, Lockpicks or events thats add to of your skills together like Breaking and Entering, Slip Away, etc.

Honed Instinct is nice to :

• add more action to your ridiculous 5-8 actions turn in some Rogues (and maybe play Pay Day if you played it during your turn by oversucceeding).
• react to a bad "advance the Agenda" (or "advance the Act", like in TCU...) by evading the monster you now have to generate engaged with you !
• simply do more to win the scenario more quickly.

The main drawback of this card is that you don't want to have it in your opening hand (at least if you can't oversucceed on your turn 1) but you don't want to draw it too late either. So it might end up as a dead draw for sometimes. For this reason I think the more card draw you have in your deck, the better Honed Instinct is (like most cards, yes I know...).

It changes a bit when you unlock new ways to use this card obviously.

What upgrade(s) to take ?

• As a general rule, you should have at least 1 "play condition" for this card that you can hope to do almost every turn, or at least half of your turns. If you can easily oversucceed by 3, don't take any upgrade that adds new play condition. If you can't, find 1 that corresponds to your deck and/or campaign. You shouldn't take more than 1 of those "play condition" upgrades except if you have too much xp.

1 □ Reflex Response. Add the following play condition: "- You take damage or horror."

• Good if you are a Rogue with 1 or if you play a heavy damage and/or horror campaign (Carcosa, Innsmouth, TSK maybe considering all the healing ?) but not TFA as it gives you damage if you fail tests which you will usually less fail as a Rogue.
• You could make it very reliable with cards like Smoking Pipe, Painkillers, Forbidden Knowledge, etc.

2 □ Situational Awareness. Add the following play condition: "- A location enters play or is revealed."

• Overall not so great, there are scenarios with very few locations or where you don't really control when a location enters play or is revealed. If you know the scenario by heart it's nice but otherwise I think the other play conditions are easier.
• Might be good in EoTE though with that many locations !

3 □ Killer Instinct. Add the following play condition: "- An enemy engages you."

• The best one for a fighter/evader ! Just evade the enemy and deal with it when it reengages you or let a Hunter enemy catch up with you just to kill him (in 1 action though) before he attacks you.
• Also good when you draw an enemy card in the Mythos phase, which is quite frequent.
• Tony Morgan will love that.

4 □ Gut Reaction. Add the following play condition: "- A treachery enters your threat area."

• Situational... Might be okay in Carcosa (if I remember correctly) and mainly in TFA.
• Might also be useful if your weakness is an enemy (or can be solved in only 1 action) ! (Trish's Shadow Agents, Tony's Quarry, Kymani's Agent Fletcher)

5 □ Muscle Memory. Add the following play condition: "- You play an asset."

• Very good if you have an asset heavy deck. Just play something and use it immediately !
• This is the most reliable of the play conditions (with 1. Reflex Response + Smoking Pipe but it needs more cards).

6 □□ Sharpened Talent. During the action granted by Honed Instinct, you get +2 to each of your skills.

• Nice if you have a specific plan with your extra action (a fighter waiting for an enemy to appear, a cluever that reveals a location and immediately investigate).
• You become less flexible because it forces you to wait for an opportunity to make a test with your action but you're better at it and you generally do not take extra action just to draw a card so I guess it's pretty good !

7 □□□ Impulse Control. You may include up to three copies of Honed Instinct in your deck. Honed Instinct gets -1 cost.

• The basic card is good so this is gooder ! And free-er ! For 1xp per card :o
• A solid "play condition" is mandatory here, so most of the time this upgrade will actually be 4xp.

8 □□□□□ Force of Habit. When you play Honed Instinct, you may take 2 actions instead of 1 (one at a time). Then, remove it from the game.

• Unless you can easily cycle your deck completely twice in a game (very possible in Rogues but you need to work for it), this upgrade gives you twice as many actions. That changes a lot of things ! Now you can fight twice the enemy engaged with you (to manage those 3-health enemies), you can play a weapon then kill that cultist in time, you can take almost a turn when the agenda/act advances, giving you a lot of tempo in those sometimes critical moments, you can engage and evade an enemy on your friend, etc.

Upgrade combinations

• "I wanted to play Ursula... :/" : 2. Situational Awareness + 6. Sharpened Talent => 3xp Twice per game, enter a new location and Investigate with a +2. It's not really worth 3xp but hey, you should have played that Ursula deck !

• "Everything is a Lupara !" : 5. Muscle Memory + 6. Sharpened Talent (+ 8. Force of Habit) => 3/8xp Play any gun/weapon, play Honed Instinct, fight twice with a +2 , hopefully kill the enemy ^^' It could be nice with the Colt Vest Pocket (0) or (2) to empty all 5 ammo in 1 turn. Also nice with Tony Morgan or Dirty Fighting (you would need a Fast weapon to not take an AoO though). Note, that it is viable with inly 3xp but the 8xp is more like a Lupara, that's all :)

• "How many actions do you want ? Yes." : 7. Impulse Control + 8. Force of Habit (+ 1/2/3/4/5 ?) => 8/9xp For roughly 3xp per card you can get 6 extra actions over the course of every scenario by just doing what you would already be doing (because you bought the correct play condition for your deck/campaign). This is obviously only relevant if you have good enough Skills or boosts to your skills to pass that many tests every turn but still ! (For this reason, I feel like Preston would fall a bit short on gas (or money !) with 5 actions, same for Jenny (without the 8/8/8/8 build ^^) or investigators that relies on assets that exhaust (Lockpicks, Mauser C96, etc.)

Final thoughts

I like this card. I think it's better for a fighter or flex than for a cluever as you might have guessed with the examples I gave. That's because, bursts of actions are generally more useful when there is an emergency like an enemy or two to kill ! But you can easily do the same thing with Investigate actions, it's just a bit too overpriced in xp for that in my opinion.

Bonus idea : Put Honed Instinct in a Sefina deck with 3. Killer Instinct + 7. Impulse Control (4xp, level 2) to play up to 6 copies of Honed Instinct per deck-cycle and nuke enemies with your spells when they approch you !