So, how can I get 100% passive armor pen as fury?

Well, you'd need a phenomenal and well designed gear set. Now, this is VERY high end, I realize, but if you'll notice there are actually a few "throwaway" gems that are being used for Strength/Crit, or other types of gems that aren't really needed. If you happen to be a JC/BS as many people are, then rejoice, because you can get 82 more armor penetration than anyone else can, which makes this even easier to get.

The goal is to shoot for the 1400 rating, and that's going to involve filling every available slot with the best item you can find that has armor penetration.

However, notice that I could have gone a little differently, because I used one trinket for hit rating, instead of getting the other armor pen trinket, and you can also substitute in something like the Scorpion until your gear is up there, since even though it won't work 100% of the time, 15-20% up time is better than no uptime at all.

I'm also not happy that this gear set has so much expertise (you need about 26, 32 is a little overkill) and I'd love to be able to trade some of that for a little hit rating (I think, and most people agree, that your minimum needed is 164 (with Precision), but since you don't cap out until 820, and your white strikes generate rage as well as about 12% of your dps, I think I'd like to have somewhere in the mid 200's, like 263 or so, but I could definitely make do with the 178 that this gear set has, and I could always use up those other yellow gem slots on more hit gems, but in this case I chose not to.

Here is a second possibility done by swapping around ranged weapons, rings etc. that has more hit rating, still goes just over the 1400 cap (and really, you could stop at 1397 and be fine, I think but I wanted to demonstrate that the 1400 cap could be achieved). It still has a little more expertise than I would like, but I'd rather have 27 expertise than 25 since you don't get fractions, so if you can't get 214 rating, go to 223.

And last, but not least, you might say, well, Gurggy, I don't have a guild that's pwning ICC 25 heroic every week yet, how can I get this 1400 cap? Well, admittedly, it requires a little bit of patience and creativity, but here's a comparison of the last choice with a gear set that's attainable, pretty much, by lots of frost emblems, and a few 25 man runs, no heroic gear, and it doesn't even count on the drops to upgrade the tier gear.

It does, admittedly, take into account completing the initial quest for Shadow's Edge, which I've already mentioned, but even taking that into account, if you're a serious raider in a serious raiding guild, this should be very doable.

Don't forget, as long as you can keep your expertise at around 214, and your hit rating at about 240-260 (minimum 164, remember) you can feel free to gem as much as possible to the 1400 armor pen cap.

In almost any set of gear you'll have, you should be looking at at least 200-300 armor pen possible just from sockets alone (or 15 gem sockets all together), maybe more. If you'll notice, this lower set of gear holds the equivalent of 19 total Fractured Cardinal Rubies, or 380 armor pen rating just in gems. Again, if you're a BS/JC as many are, you can notch this number up another 82. So even in this set of gear there is still some play to move things around. You'll notice a couple of what I call throwaway gems that are Str/Crit gems.

Also notice that in each case, I've satisfied the metagem conditions with two puissant dreadstones, and also fulfilled the 4 piece tier 10 bonus, even though this was entirely optional (some of the tier pieces could have been traded for higher armor pen pieces that didn't budget in the set bonus, but eh, why not?).

Fourth version, even easier, uses a better + hit rating trinket that isn't as cool, but can be bought for emblems of triumph.

Fifth version, trades low drop rate Flame Leviathon thrown weapon for badge one.

Last one. I think this one may be my starter Armor Pen set. I already have many of these pieces, and most of the rest I can do as I acquire more frost emblems, and I only have 4 drops that I have to hope for in ICC 25. The catch here is that the hit rating is lower than I'd like and the expertise is way too high, but without doing 25 Ulduar or some other raids that will be difficult if not impossible to get people to go for, this may be my best bet for now (of course, it still hinges on getting down more bosses in ICC 25, but I have faith in my guild. Even when we struggled at things before, we eventually overcome.

Here is my transition chart so I can follow along.