There are a few good synergies here to bring up. First, Minh and any version of Grisly Totem.

With Minh, each one of these can be +2 Wild, therefore making it roughly equivalent to 3 Unexpected Courages, which you can pull back from discard at will. That's honestly pretty great, and at its best, is pretty close to a never ending stream of Unexpected Courage.

With Grisly Totem, you'll get the exact same effect. If you have the Seeker Grisly Totem, you could even be drawing a card each time as well.

With Minh AND Grisly Totem, you can stack those effects. That means you'll be able to get +3 Wild icons, 3 times, on a card you can pull back to your hand from discard for 1r.

Of course, to maximize these interactions, you want to commit one and only Glimmer per round, as these abilities have per round limits.

Keep in mind that pulling back 3 Glimmers at once is a burst of 3 cards in your hand. This can empower other effects which note how many cards are in your hand, such as Curiosity, Higher Education, and so on.

Outside of Minh and Grisly Totem, the other great use of Glimmer is as discard fodder for something like Wendy, Pete, or Cornered. You can happily chuck these cards into your discard pile whenever and draw them all back when you need to. Of course, other cards are discard fodder (Winging It, et al.), however those cards can't bounce back into your hand nor do they have icons in case you need commitments. Due to its easy recursion and flexibility of use, Glimmer is the most reliable discard fodder currently in the game.

Soloclue covered the best uses for Glimmer, but I want to talk about its individual effectiveness when those synergies aren't available.

The first thing to note is that all symbols aren't equal. Depending on the makeup of the chaos bag, being 1- or 2-over the threshold can have drastically different odds of success. Meanwhile, being 3-over won't improve your odds at all if there are no -3s in the bag. In a lot of cases, committing a +1 to three tests is much more useful than committing a +3 to one test. It lets you sit at a comfortable chance of success and avoid the many "-2, if you fail do X" penalties for drawing symbols.

Glimmer of Hope's utility is in ensuring you—and your fellow investigators—hit that comfortable target as efficiently as possible. As a recurring +X to tests, it's comparable to a pump asset like Dig Deep, with a few advantages (and limitations). While pump assets cost two dollars and an action to install them up front, Glimmer can be played out of hand and is paid for only when you need to recur it. If you draw a Glimmer in the upkeep phase and immediately need to use it, that's fine. Glimmer is also a wild symbol, whereas pump assets only affect two skills—and in survivor, neither available pump asset affects . And while pump assets can only boost your own skills, Glimmers can be tossed around to other investigators' tests.

However, Glimmer suffers in a few ways. Most glaringly, their usefulness depends on how many you've drawn; recurring a single for a dollar and an action is a terrible exchange rate. Drawing two breaks even, but ideally you want all three; without heavy card draw, that can be difficult. Also, the cost of an action and a dollar isn't quite the same as two dollars for the equivalent boost from a pump asset. Depending on your economy you may find yourself with an excess of cash, especially late in a scenario, but you will rarely have an excess of actions. And finally, while a pump asset can hit any threshold(s) with enough cash, Glimmer has a hard limit of +3 to a single test. There's no way to bank more, and recurring the +3 for a second test provokes opportunity attacks.

So is it good? As established, with Pete/Wendy/Minh or a Cornered deck, it's great. With a lot of card draw or a scenario where you expect discard effects (e.g. Dunwich), its good. Silas runs cheap and focuses on combat, so he generally prefers Scrapper/Scrapper. Preston hates it. With anyone else, it's really down to preference, with a slight edge if you're playing multiplayer.

I'm trying to build a rich parallel "Skids" O'Toole deck and at the beginning of the campaign this card is interesting: if I have no copy of A Glimmer of Hope I test 3 against 1 for a benefit (if the test succeeds) of 1, with a single copy I test 4 against 2 for a benefit of 2, with 2 or 3 copies I test 5-6 against 3 for a benefit of 3.

And once I have all 3 copies in my discard pile, each round I spend an action and 1 resource to get the 3 copies back to my hand and then test 6 against 3 for 3 resources. A benefit of 2 so not as great as an Emergency Cache.

But if the whole deck revolves around getting resources to have bonuses, The Black Fan gives a passive +1 and I have to pay to retrieve A Glimmer of Hope less often.