I usually slot one of these in my Jinteki decks because I found it very versatile and useful in several ocassions. For glacier or horizontal jintekis. By these days I use it for the following

  • Put a used Snare! in my hand. Install the same snare and an agenda.

  • Make the same trick with an agenda as Fetal AI or Obokata Protocol if I haven't avanced them yet. Or if I have just drawn the Mushin No Shin to play them next turn.

  • Put the Snare in your hand and make your hand more scary. Install ice in other places.

  • Avoid Femme Fatale tokens. Install the same ice or another one.

  • Remove a Mwanza City Grid that has been already useful.

  • Just install scary ice in a remote server with already lots of ice without paying anything.

I haven't tried to export it to other factions yet, but the Jinteki mind games are more difficult to import and with a 3 influence is harder to justify.

Gatekeeper is strongest when it was rezzed this turn, so it would combo with cards that allow you to derez your own. Cards that help you get more activations from the rez strength ability are needed to help combo.

Bioroid Efficiency Research makes it so if the runner does break through, you get another shot at the rez strength.

Divert Power makes something cheaper while you get to trigger this rez strength again.

Test Ground allows you to fire the trash ability, derez Gatekeeper, and then re-rez Gatekeeper with unexpected strength.

Plus, Gatekeeper is cheap and might give you some recursion of used cards if you can catch the runner flat.

Is it for every deck? No. But it might have a place in some.

Great first review. You've highlighted —
some good combos. Just note that Bioroid Efficiency does not work as Gatekeeper is not a bioroid ICE. In addition, Blue Sun is also worth a mention! —

Rules doubt.

Does lucky charm also work for any subroutine (for example a wall of static or vanilla)? Or just things that say "end the run" that they're not from the corp?

Are subroutines card abilities?

Yes, that is correct. It can be used against WoS or Vanilla or any other normal (single) ETR sub. —

A weak but tenacious code gate for Weyland! I've seen a lot of this due to rampaging Hippos and hungry Maxxes with Spoons destroying ice left and right, because this can't ever fall prey to those if it's correctly placed on HQ. Anywhere else and this is diet Enigma, so please don't do that.

This one REALLY hoses Anarchs running Black Orchestra (aka all of them), they pay 3 to break and still have to hit the first sub to even get a look at HQ. It's a minimum cost 3 for pretty much every Decoder, which is solid for a 3 cost ETR. It slots in just about any Weyland deck that wants to discourage frequent HQ runs!

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Nice! I never considered the fact that it's immune to cutlery and Hippo considering you can't break all its subroutines on HQ. —

Diesel gives you flames.

Blueberry Diesel only gives you TM.

It's fine draw in-faction for crim, I guess, but the design couldn't possibly be less original. Obviously.

FFG gave each faction a "draw three cards" card:

  • Shaper has Diesel. When they need more ideas, they chug energy drinks... because they are nerds.

  • Anarch has I've Had Worse. Anarch gets new ideas as a result of being abused by the Corps, and the card triggers for free when you are damaged. Very thematic, very strong.

  • Crim gets Fisk Investment Seminar, because for a criminal, what better way to get ideas than scamming the corp into giving you some? And yes, maybe the corp gets some new ideas too, but hey! You're a criminal, just steal them also!

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Yeah, I don't want to be immediately negative about the card, but from my perspective, it's just a strictly worse Diesel. Diesel shows you 3 cards, and if you're not wreckless, you play it on click 1 or 2 so that you have enough clicks to respond to what you draw before trashing having to discard them to get down to hand size. Blueberry Diesel (BBD) let's you see two cards (okay, information) then select which one you don't want. Then you draw 2 cards. If you had just regular dieseled, you would have just drawn all 3 cards anyway, so who cares about the filtering. I feel like BBD should have let you draw 3 cards, add 2 of them to the bottom, then draw 2. —
But BBD is in faction for Criminals :), Diesel is not. I like it! —
That's fair--if you're already in Crim, it's an influence-free draw option. —