By my estimation, this is a very powerful card for any / deck. Spell charges are precious, and this allows you to replenish them safely (as opposed to Recharge) and almost assuredly. This translates to 2-3 damage (Shrivelling and its upgrades) or 2-3 clues (Rite of Seeking and its upgrades) per Enraptured when they are most desperately needed. Many investigators, such as Norman Withers, Carolyn Fern, and Agnes Baker rely on Shrivelling charges for defense and reliable damage output, and this card allows you to spend those charges more freely by extending the life of the targeted spell.
If this skill test is successful during an investigation, place 1 charge or secret on an asset you control.
Voyaging far from our placid island of ignorance.
The Boundary Beyond #157.
It seems like a hard card for Agnes to use due to the Intellect symbol. — Chobabot · 1
She doesn't need to be the one performing the test. In particular she could toss this into her seeker's check and still reap the rewards. — madhatter152 · 3
Can also toss this on a Flashlight investigation of a low-shroud location (your own Flashlight or someone else's) for a ~95% chance at the extra charge. — CaiusDrewart · 1580
I do think I prefer Recharge once enough extra XP comes in--I think a ~70% chance at 3 charges is superior to a 95% chance at 1 charge, even if Recharge costs an action. That's simply a lot more raw power from the card. Especially since you could, if necessary, help Recharge out with something like Premonition, Time Warp, or a Grotesque Statue card. (Now, obviously it isn't fair to Enraptured to compare it to an XP card; I agree that Enraptured is pretty good.) — CaiusDrewart · 1580
*a Grotesque Statue charge. — CaiusDrewart · 1580
The more cards are release, the more "value" each deck slot has. I'm not sure 1 charge for a spell justifies a whole card. — Django · 2200
That depends Django, for characters that depend wholly on charged spells the one extra charge can mean the difference between being able to garb 2 clues off of a major high-difficulty location, or not at all. Agnes and Akachi can definitely put this to use in combination with Flashlight — Tsuruki23 · 884