Using with Amanda Sharpe deck and investigate to high shroud location Because this card would commit to all Investigating and Encounter resolve You get the following

• Investigating - 1 Blessing token for 3 times (Repeated from her ability)
• Treachery card test - 0 to 2 Blessing token for 1 times (Enemy or some card may have no test)

For my use I can add around 3-8 Blessing token in a single round.

That's promising because you can try to add more if you found higher shroud location

If you know Ragnarok Online (damn I feel old), this card turns your into a Soul Linker. Kinda sad alone. Selfless and painful to build such a character (takes a chunk of 5, 10 XP from your plan). But it unlocks a special ability differently for each character that make their mouth water.

+X effect became strategic (can "snipe" an exact disadvantage number and win), turning into a kind of pass-a-test effect you usually see in Exile card. For example, Agnes Baker gets a boost for each horror. Normally you will not think "Let's take this test at 3 disadvantage. I have 3 horror. If I get , I pass the test!", you will boost to at least equal or higher before taking it. Therefore these effects works no different from 0 token in a character without over-succeed mechanics. With this card, your current horror count becomes strategic element. Basically turns Agnes's ability into something like : "If you take a test at disadvantage no higher than your horror, this test is automatically successful. (limit once per game)" Now that sounds a bit better.

But, these success sniping for "pure +X" investigator aren't the core target of this card. The highlight is when it also has situational side effect that was normally left to being doubly lucky. (Lucky to get in the first place, and also happened to benefit from it.) This card can give new look to the ability. I have looked at some that seems impactful beyond succeeding a single test :

• Core
  • "Skids" O'Toole : Guaranteed +2 resources since you can plan for success. You can chain into something you lack 2 resources or less on your hand, like expensive Event you need to use mid-fight.
• Dunwich
  • Zoey Samaras : Automatic damage depending on your weapon +1, at up to -1 disadvantage. Aims for an exact killing blow at will.
  • Rex Murphy : Can plan to perform a test that is inconsequential to failure to draw 3 cards. (Or benefit from failure, like Rabbit's Foot)
  • "Ashcan" Pete : Deal 2 "automatic damage" with Duke as long as disadvantage is no higher than 2, with potential for an attack and one more discard-ready attack that you can put in your commits. (Just Duke 3 times in one turn without ammo limit.)
• Carcosa
  • Minh Thi Phan : Try and Try Again that works for everyone. Snipe the over-succeed criteria for the powerful 2XP Dunwich commits with the +1 and even get them back.
  • Sefina Rousseau : Compress actions and plan with all your events. (e.g. Start with evade and immediately get an event that do stuff to exhausted enemy.)
  • William Yorick : Revive a card without any limitation at exact timing you want, like 1-2 XP Guardian events/skills that Resourceful cannot get.
  • Akachi Onyele : Anything with 1 charge left can be used twice, or leading into something that was previously out of charge.
• The Forgotten Age
  • Ursula Downs : When you know you have to move away after, e.g. after getting the last clue.
  • Finn Edwards : Make sure you get 2 over and make sure there is a clue to pick.
  • Father Mateo : Plan for a turn that an additional action matters.
• The Circle Undone
  • Joe Diamond : Pop after you just used high value Insight.
  • Diana Stanley : Pop after you just used high value cancels.
  • Rita Young : Make sure you can take advantage of an entire round limit, e.g. pop in mythos phase.
• The Dream-Eaters
  • Tommy Muldoon : Make sure you have 2 damage/horror to move and also a target of the move.
  • Patrice Hathaway : You can be selective on timing to reset the deck with good stuff you just used, or after you had dealt with the weakness to left it in the discard.
• Innsmouth
  • Trish Scarborough : Make sure that this is an investigation.
  • Dexter Drake : Plan the shenanigans in higher complexity.
  • Silas Marsh : Pick a special effect commit since you already know you will succeed. (by what amount)
• Edge of the Earth
  • Lily Chen : Supercharge Discipline which has a built-in test to be usable twice, knowing it will flip back right now.
  • Daniela Reyes : Merges the Mechanic's Wrench to her effect. You can tailor made any custom follow-up attack knowing that it will automatically succeed, in addition to her regular counter attack tricks.
• Starter
  • Nathaniel Cho : When you have high value event to get back.
  • Winifred Habbamock : Plan for multiple of 2 point over-succeed.
• Scarlet Keys?
  • Carson Sinclair : Stick to someone that is going to get -ed.
  • Amina Zidane : Make some doom plays in comfort of knowing you can then drain all of them to Sin-Eater to eat?
  • Charlie Kane : Pop on an exact test that you exhausted Bonnie Walsh. Make multiple plays with Chuck Fergus, Michael Leigh, etc.
  • Vincent Lee : Make sure there is something to heal.

A little trick with this card is that the enemy exhausts after making a normal attack in Enemy Phase 3.3, and the check of this card came at the end of enemy phase. Therefore if you are already fighting an enemy and see that the damage taking is inevitable, you can attach Hiding Spot on your location. It is not destroyed while the enemy is busy attacking you.

Therefore playing this card can prevent a new enemy spawning onto you while you aren't quite finished with the current enemy yet, since the new enemy gains Aloof and you are messing with the previous enemy inside the hiding spot... If nothing spawns then you still get the spot saved up for use in the future.

It also gains Aloof, which is not useful if you are already engaged, unless you evade it, in that case you have an advantage of evading on the final action, not having to move away. Fast attach timing can be as late as after Hunter enemy moves, so you can see the result of your evasion attempt first even if it was the final action.

6 XP feels substantial, but if you stick 3 high XP event cards on it, now it is like you no longer need to buy 2x copies of them. The more expensive, the more XP savings.

Even if they aren't quite adding up to 6 XP, still 2x copies won't offer perfect consistency. (but offering a chance to potentially use the events 2 times, as opposed to buying 1x to stick.) Even, even so, 1x copy to stick has an advantage that you have more deck space to do something else, and these 3 event cards are thinned out immediately, then improve consistency of the other 2x copies / your signature card a little bit.

(Underworld Support thins out 5 cards on highlander penalty and you can feel the impact of finding signature/exceptionals/1x purchases faster, this card which thins out 3 could also be think of as a lite version.)

As mentioned by toddwords, this card is expensive at 2 resources. The 5 XP version is amazing but only if you have that much XP available to spend. I sometimes wish there was an intermediate XP version and now there is - sort of: Parallel Fates. Of course, not every investigator with access to No Stone Unturned has access to Parallel Fates and taking Parallel Fates won't get you any credit toward No Stone Unturned but it is an interesting upgrade to consider.