Anyone who’s played Caduceus enough can tell you full well how often an unpumped trace-2 ETR subroutine is unsuccessful if fired. Given that nowadays, many runners are packing link due to dangerous threats like Exhibit A or Exhibit B, that trace-2 ETR can end up costing the corp a lot more than they paid for. However, anyone who’s ever played Resistor can tell you how often their trace-4 ETR subroutine is successful (if not broken) and how valuable it is at a great rez cost.

My point is that Surveyor is valuable as soon as soon as you can get X = 4 (making Surveyor have ICE/trace strength of 4). This is because it immediately makes the (arguably) top 4 killers in the game very, very sad:

• Out-of-range for Mimic without support

• 5 creds for Na'Not'K (which will never have more base strength than Surveyor as long as X > 2)

• 5 creds for Mongoose

• 6 creds for MKUltra

This is pretty good at a 5 rez cost and letting both subs fire can be expensive to pay through (Power Tap builds aside) or game-ending. There is a catch, however – Surveyor needs support from an additional piece of ICE to get X = 4. Which makes Surveyor quite difficult to play early game since it’s got a huge upfront of having an additional ICE installed + its own rez cost of 5. The immediate synergy that comes to mind is pairing this bad boy with Jinja City Grid or other installation-support cards.

But what about when X > 4?

• Mongoose is awkward since it only boosts cleanly to odd-number strengths while Surveyor will always be at even-number strengths. This means Mongoose will be saving 1 credit from its break subs ability but will be losing 1 credit from having to over-pump

• Na'Not'K will always require at least one pump at its awkward 3-for-2 ability and will require one more pump for every additional pair of ICE on the server

• MKUltra is in the same bin as Mongoose since it only pumps cleanly to odd-number strengths. It’ll require X/2 pumps to get past Surveyor and that really gets out of hand as soon as X = 6 or more

• Mimic, git gud kid.

TL;DR

Cards like Surveyor are the finale in the Kitara cycle's plan to rejuvenate the Glacier archetype (although ICE destruction being back is a thing so maybe not). It's also an easy target to splash into other Glacier builds at its 2-influence cost. A good face-check ICE, a better taxer as soon as you can make X >= 4 but one that should not be used for more rush-based play. Just don't let Security check on Surveyor.

One of the only ices in the game which is both a fierce facecheck and wildly efficient. It currently (2021) has no bad matchups* and in glacierish decks it is almost always useful. It pairs well with any other ice and generates unusual amounts of value out of cheap ice installations.

• Even with no other ice in its server, it's a reasonable early rez against a 0-trace runner. (In tournaments roughly 75% of runners are base-0).
• With one other ice, it is numerically comparable to Mausolus (itself a great ice). It'll cause a 4+ credit impact if they have a breaker and a 6-8 credit impact if they do not.
• With 2+ other ice it is usually one of the most expensive ice in the game to break conventionally and its subroutines are must-breaks.

UPDATE: More recently (May 2023) there are many cards flying around which can break 2 subroutines regardless of strength. Endurance has been recently banned, but Boomerang and Botulus are still in play.

*Except Tao (3% of runner decks) and Smoke (9%). In addition, a few runners have a base link which makes Surveyor less valuable early, notably 419.