While this card is very bad economically, there might be some use for it. If you can somehow get this behind two different pieces of ice, and then destroy the runner rig, it might take them a long time to recover. The main issue with that plan is that if you have two different pieces of ice, and the runner don't have a rig, just scoring agendas is usually a better plan. The only time I have had it work for me was in conjunction with Project Ares. My opponent where convinced it was a trap, so I got it up to like 10 counters, got a crackdown up to one and scored the Ares. Sadly Project Ares is also a bad card.

Against runners that don't care much for remote servers, this might be a way to punish them, but probably not much, as they can just ignore it in a lot of cases.

Has anyone figured out why this card exists and why it costs one influence? As it stands, it has a similar effect to Deuces Wild. Typically people play DW and net 1 and draw two cards. But DW can be used for other things. Save 2 (or more) s by removing a tag. Or make sure you can get into that juicy server before committing to the run. More importantly, (at least for a little bit longer) you can make DW better with Prepaid VoicePAD. No such possibility with Build Script though.

If it was influence free, I might include a couple in a Criminal deck to help with draw. But because of the influence, I doubt I'll ever play it.

I'm not even sure it'd help much with draw. It saves you a click but it takes up a card slot, probably multiple if you want to have it on hand when you need it. And the 1 influence makes it indeed a non-starter. —
It's usable from 0 credits is the main reason, so it can be used when you're broke. —

So, everyone has seen the MCA-Corporate Troubleshooter combo that hasn't had an errata yet......so CTM just gets significantly better. Obviously MCA is also great for A-a-Ron and other game changing resources. Let's take advantage of this card while it's so powerfulate! Not sure what else to say. Good day.

[NOTE: The following was written while I was under the impression that the extra accesses remain after the run. This is not the case as the UFAQ explains. I'm leaving this up for now so the comments make sense but please be aware that it's almost entirely wrong about the value of the card.]

Multi-access is powerful and there aren't really that many cards that provide it. Severnius Stim Implant is a powerful new tool, at 4 influence effectively only for anarchs.

It's a bit of a complicated setup. You first install it. Then at a later point you use the ability to make a run on R&D or HQ. At that point you have to trash cards from your grip (you choose which ones). For every 2 cards you trash you will access another card from the chosen server from this point forward. The run does not have to be successful in order to get the extra access(es) in the future and the extra access(es) already happen in the run you make with Severnius Stim Implant.

Severnius Stim Implant is hardware so it doesn't suffer from MU limitations like programs and isn't as easy trashable with tags as resources.

As I read the card you can use the ability multiple times and the effect stacks. You can even use the same stim implant on both R&D and HQ and they each have their own tally. So you can run on R&D, trash 2, get one extra access and in the future run on HQ, trash 4, get two extra access on HQ while keeping the existing extra accesses from Severnius Stim Implant on both R&D and HQ.

This is great. The big downside of Severnius Stim Implant is that you do a run with a reduced hand size which is potentially risky. Building up your extra accesses over multiple runs reduces that risk.

Comparing Severnius Stim Implant with Medium for R&D multi-access Severnius is weaker in the long run. If you can consistently get multi-accesses on R&D Medium will eventually snowball into a victory while Severnius doesn't profit from extra runs. Severnius does let you access extra cards in the run that charges it, which can be useful if R&D isn't easily accessible.

Medium of course doesn't let you do multi-access on HQ and it's here that Severnius Stim Implant really shines. Accessing 2 cards from HQ gives you a good shot at accessing agenda's, accessing 3 cards from HQ makes it likely you access agenda's even if there's 1 agenda on a full HQ. And 3 card multi-access with Severnius Stim Implant isn't really that expensive, trashing 4 cards from your hand, possibly over the course of two turns. Criminals have events like Legwork which give the same multi-access boost as a 4-cards-trashed Severnius Stim Implant and the soon-to-be-rotated HQ Interface is the same as Severnius Stim Implant with 2 cards trashed.

The closest thing anarchs have to Severnius Stim Implant for HQ is Nerve Agent, but that one will cycle out soon.

It's hard to predict how strong a card will be in practice just from static analysis of the card pool but I'm going to call Severnius Stim Implant a near-staple in anarch decks in the future. As a multi-tool for R&D and HQ accesses it's flexible and meets a demand in nearly every deck. The cost is slightly painful but nothing anarchs aren't used to (Faust). There's no obvious and widely counterplay to Severnius Stim Implant like there is to Medium in the form of Cyberdex Virus Suite. All that raises the power level of Severnius Stim Implant, though I don't think it's at the point of being overpowered.

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At present (see UFAQ) the ability only applies during the run it initiates. It doesn't stack and works like other single use click ability runs, e.g. Keyhole. —
Yeah, it'd be crazy if the effect persisted after the run it was used on. As it stands, I see myself trying this card in conjunction with Emptied Mind. I've tried to make that card work a few times and have not had a lot of success. This might make it work though. —
Ah, ok, so the UFAQ is already there when the ANCUR page isn't up yet. Good to know, thanks. This info does blow my whole review out of the window, considering it I'd rate it somewhat underwhelming unless you can combine it some some kind of card that has beneficial effects when you trash cards from your grip. —

MCA Informant can (at the time of writing) be installed on Corporate Troubleshooter. This is very, very bad. The runner has a permanent tag until they run and trash the combo... So, as usual, a HB card means NBN wins again.

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I KNEW IT that this Connection subtype is there for a REASON! —
Wow, it's even somewhat official: <http://ancur.wikia.com/wiki/Station_One_UFAQ#MCA_Informant>. That's a rather painful miss during card design. —
I don't think it is an omission. Since it is terminal, the Corp still has to wait one whole turn before he blasts the Runner to bits. The combo itself is fascinating, though I have my doubts if it is balanced and makes sense thematically. —