NBN finally got their "god ICE". Taking his place next to Susanoo-no-Mikoto, Orion, Wotan (and maybe Fairchild) we get to see NBN's answer to giant, unique server protection.

And much like the other pieces of god ICE, I'm not sure how much Thoth will actually get used. It has a lot of weird extremes.

• It's only moderately punishing on facecheck. It gives you a tag, a single damage, and loss of a single credit. Annoying, but not crippling. (I would totally run through it, if I thought there was an agenda behind it.)
• The traces are only strength 4, meaning that high-link runners (basically anyone using security nexus) can ignore the subroutines.
• The strength and break cost are actually pretty good, for the rez cost. Mongoose takes 7 to get through this, MKUltra takes 9, and even things like Golden or Garrote cost 6. (And still take a tag.) Not bad for a 7 rez.
• If you can avoid the tag, (and aren't already covered in tags) then you can basically ignore the whole ice. New Angeles City Hall and Hunting Grounds make this ice sad.
• It does give tags, just for encountering it. That's moderately nasty, if you don't have tag prevention.
• It combos nicely with things like Data Ward, Pachinko, Quantum Predictive Model, and Keegan Lane.
• It doesn't actually end the run.

All in all, I feel like it might just have too many downsides. Runners are packing (being forced to pack, really) a lot more answers to tags than they used to. High link is becoming more and more common. It's got some nice tax, if you can make them feel like they have to break it, but it's also really easy to just clear the tags, and accept the 1 damage/credit tax every time you want to get through.

If this card had come out a year ago, (say, around the time Data and Destiny was landing) then I think it would probably see some play. As it is now though, I think it's going to be hard to justify. If you want tax and/or ETR, Tollbooth is still the gold standard. If you really need one extra on-encounter tag effect, then you might be able to use this as your 4th Data Raven, but otherwise, there are better pieces of ICE.

Thoth is mainly useful for a tag on encounter, which I'd value at 3 credits of damage (+$2 earnings for Reality Plus, the ID where this is most widely used). It's usually cheaper for the runner to let the traces fire, so I'd value 1 net damage + 1 credit lost at another $3 of damage. An 8 credit swing for a 7 cost ice is excellent in Reality Plus. In Reality Plus, this is a significantly better ice than Funhouse. The extra $2 in rez cost is well-compensated by the runner taking a tag rather than having the choice to end the run.

If you're playing heavy on tags, you'll have a phase where you're trying to land tags and hopefully a "tag me" phase where the runner is willing to take a lot of tags and just go for it. This is the only tag ice very useful in both phases. At the point of the game where Funhouse is useless because the runner is already super-tagged, Thoth is potentially lethal and/or at least very costly.

Problem: the ice is unique, which makes it very inconsistent. Still, if tags are valuable enough to you that you're running 2+ Funhouses, including a Thoth is economically sound (assuming the Funhouses are).

Placement: I'd slightly favor RND over HQ. When the runner is super-tagged and you're trying to close out the game, I think the flailing runner's best chance for stealing a win is hammering a central, and Thoth will limit their options there. I don't think Thoth is as good on remotes. PS: Unlike Funhouse, Thoth is excellent against Turning Wheel farming and works much better as the outer-most ice.