One of the more useful things for a Runner to know in Netrunner is what ICE could show up when they make a run, and how bad it could be. This gives them a chance to plan when to run based on what sorts of nasties the Corp could drop on you. So, let’s look at the different thresholds of bits the Corp could have and what nasty pieces of ICE they might spring on you at each. Note: I am focusing on the nasty ICE at each level, and ignoring some of the less pressing ICE like Chum since it only makes other things worse rather than being a threat in its own right, or TMI since it’s the same effect as others at the price point. I will be focusing on exemplars/worst case scenarios for each price point.
Free and Clear. Sure they could rez a popup window, but it only takes a bit to get past. You are free and clear to run on unrezzed ICE if the Corp is broke. Which is the reason people like account siphon/vamp. To force the issue.
Draco, Chimera, and Ice wall. Worst case your run stalls. Go ahead and make them pay for things as you’ll most likely get in to the fort, and worst you now know what it is.
Enigma, Wall of Static, and Viktor. Run early. If it’s Viktor you’ll want the click to break the brain damage, but otherwise all you need to worry about is end the run.
Neural Katana, Rototurret, Archer, Data Raven. This is where things start getting dangerous and it really helps to known what to fear. The Katana is likely only going to show in Jinteki, while Rototurret is easy enough to splash anywhere (and worth it for the Corp) Meanwhile Data Raven’s only scary if you’re concerned about tags (and the bags that might follow) while Archer is worthless without an agenda to toss but really nasty with.
So, advice running against 4 (or more) bits: in case of Rototurret and Archer’s program trash make sure you either have a sentry breaker or no programs you care about. (it sucks to drop Magnum Opus to then face plant into turret. Drop Opus post-run). The Katana simply needs 3+ cards in hand. You still even make it into the fort. And Data Raven even gives you an out in itself if you care about the tags. (If you don’t it doesn’t stop you)
Ichi. Two ICE. Since the ideal Corp first turn is ICE R&D, ICE HQ, and gain a bit, Runner first turn will often be starring down two ICE and 6 creds. Thus it is a special case to be aware of: First, Ichi 1.0 could show up. Luckily he’s Bioroid ICE so if you run early you won’t care too much, and the two program breaks probably won’t matter too much first turn. Hitting first turn also isn’t that scary since even NBN can only bump the trace to a 4 if you don’t click break the trace. So, not really scary, but another reason to be running early (especially on the first turn).
The main thing, though, to worry about with 6 bits and 2 ICE is the Corp’s ability to get both. Worst case for your they have two of the 3 cost, or an Ice Wall and any already mentioned ICE as they can protect both servers. But since even that will deplete their funds and likely only stop you (while letting you know what breakers to get) it’s worth it to run against those first turn ice. Worst case scenario it’s two Enigma so you spend your whole turn to bankrupt the Corp and learn what his defenses are. Knowledge is power, so spending a turn face planting to find out what ICE he has is often worth it.
Tollbooth, Wall of Thorns, Heimdall. This is where things start getting scary. The worst ICE in the game are almost all 8 cost. Where any lesser bank account is usually worth probing blind, 8 bits means you need to do a little thinking. Make sure you keep at least one click to stop brain drain from Heimdall. And be prepared to not make it in and lose something more if it’s either of the other two. That said, 8 is a large sum so it’s still worth it to fight against the ice even if you’re not sure you can break it, since you may just ruin the Corp’s advancement plans for a turn, or put him short stack enough to get impunity on other forts.
Janus. Something has gone horribly, horribly wrong if the Corp is this rich, but sometimes things happen. While very rarely out of faction, an HB player with a giant stack could easily brain drain you if you’re unprepared for it. So, if they have a stack of creds and are giggling uncontrollably to themselves over some piece of unrezzed ICE make sure you want in that fort before you risk the total face plant. Of course, you win the game by stealing agendas, not preventing damage, so even if you’re sure it’s Janus it can be worth running if the game’s about to end anyways since he won’t directly stop you.
As always with Netrunner, the biggest key for the Runner is knowing what the Corp is capable of and planning accordingly. Hopefully this will help you prepare for the unrezzed ice they might throw in your way. And always be mindful of the new data packs as they will add more ice you need to be aware of, though I imagine the thresholds will remain mostly in tact. As a balance matter ICE power is usually tied to cost to rez, and this can be seen in the newer pieces we have received such as Chimera or Popup window.
All that said, never be afraid to run against unrezzed ice to learn what it really is. You win the game by stealing Agendas, not by never taking damage.