Limited applications, but say Darrell Simmons fails a skills test on a Seeker Asset by 2. Granny Orne intercedes and he’s down only one. He immediately triggers the reaction on his Lab Coat to pass by zero. Could be worth the setup if you’re already recurring Fingerprint Kit, on a higher difficulty, for example.

A sequel to all the fight/evade reduction cards for Exploit Weakness, lets do the same for Shed a Light:

Guardian

• Breach the Door (The Scarlet Keys)

Seeker

• Arcane Insight (Path to Carcosa)
• Cryptographic Cipher (The Innsmouth Conspiracy)
• Map the Area (The Scarlet Keys)
• Otherworldly Compass (The Forgotten Age)
• Vantage Point (The Forgotten Age)

Rogue

• Momentum (Dream-Eaters)

Survivor

• Gumption (The Scarlet Keys)
• Lantern (Path to Carcosa)
• Lantern (2) (Return to Path to Carcosa)
• Old Keyring (Stella Clarke)
• Old Keyring (3) (The Scarlet Keys)
• Quick Learner (Stella Clark)
• Winging It (The Forgotten Age)

Neutral

• Flashlight (Core Set)
• Flashlight [lvl 3] (The Scarlet Keys)

A few notes:

• The Skeleton Key is very temperamental with Shed a Light. It sets the shroud to 1 after modifiers, so things like The Skeleton Key into Flashlight won't work. What will work is The Skeleton Key into a difficulty reduction effect, not a shroud reduction effect. So The Skeleton Key into Map the Area, Momentum, or Gumption (or Flashlight (3) amazingly, since the upgrade now reduces difficulty instead of shroud) does work to get a location's shroud to 0. (Edit: Thanks for corroborating this Dscarpac.)
• All these cards pair very will with a second keystone card: Lola Santiago. Take both her and Shed a Light for extra likelihood to get combo value from shroud reduction.

This card is the best for Patrice Hathaway and makes her nearly invincible since she always gets "heal" back at 5 cards during upkeep phase. Moreover, this card can help her utilize useless cards in her hand every round.

Also, if you don't want to deal with Watcher from Another Dimension and are happy with 4 cards each round then Idol of Xanatos can be extremely helpful.

While Michael was printed in Edge of the Earth, he actually seems like he was (at least partially) designed to work with one of the Scarlet Key investigators: Charlie Kane.

He's not bad in other investigators, see the other reviews for that, but he's well worth consideration in the politician. He gives two static boosts and soaks a ton, plus his first doesn't exhaust, so on turns where you're not fighting he just gives you a nice big bonus.

Additionally, because Charlie is limited to only level 0-2 non-Ally cards, it can be hard to find big pockets of damage for him. Events can be one way, but Michael Leigh offers another solution by turning your 2-damage .45 Thompson into 3-damage Lightning Gun. And using Bonnie Walsh, you can potentially get this bonus damage multiple times in a turn when fighting bosses.

While the 5 XP is certainly an investment, I think that players looking for a "fighter" archetype Charlie could seriously consider Michael.

Played this in my latest Harvey Walters deck and it was kinda insane. Since it's a new card, i wanted to test it a bit and see how it is in practice, because i was not very warm about it, but it proved to be very valuable. In the end i had 6xp in it as it was just pure value. I took Refined+Empowered and 5 times i gave my friends 4 cards for 1 action, which is just ridiculous for Guardians or Mystics as they generally do not draw as fast as Seekers or Rogues.

All in all i was very pleased with it, it does bother me a bit that it takes up a hand slot so i could not run my trusted Magnifying Glass + Occult Lexicon, but my group could handle enemies easily so i could swap my lexicon for this, and in the end it proved to be the right choice, since giving my Guardian 4 cards couple of times is enough to make him draw all of his best cards and deal with enemies