Hey, This is Falkenbcrg with my second build. This time, it is my former main champion, though bare in mind, that my build has changed a lot and this is just it's current state, and will change as time goes on.

This build focuses on a more tanky Warwick, but still able to dissh out the damage.
Also this build is very focused on a particular role in teamfights mid/late game, but more on that later.

First, the runes.

For my marks i take Greater Mark of Desolation so i can more easily shred through lower armor targets, and help take buffs, and is also useful for general damage.

For my Seals i take Greater Seal of Defense now this is a bit self-explanatory. I need the armor to tank better, and i take armor per level, since (again) this is more of a Mid/late-game guide.

For my Glyphs i take for reason, look at reason for seals, and replace armor with magic resist.

For my Quintessences i take mainly because of his passive, but also just for all around damage output, and trinity procs.

For my masteries i take 0/21/9 because i am a tank, so i need to stay alive and interrupt and hurt.

For my items i start off with a Since it gives me a lot of sustainability in lane.

Next i go for and a Since they give me sustain, money and movement to potentially gank, or just avoid getting ganked.

Next i pick-up and Philosopher's Stone For the same reason as the last two.

Now that you have some sustain and money flowing in, you want to start building some of the bigger items.

Next up i get Wriggles Lantern and because these are very good items and are very cheap for there utility, especially the free ward you get from Wriggles Lantern and overall just very good items for Warwick.

Now we start on the more expensive items.

I get for the insane amount of stats it boosts as well as the two procs it gives you.

I now start building my last, more defensive items.

And

For my skill i max out for the life steal, after that i max out so i can chase people better. And lastly i max out

For my summoner spells i take (ofc) and as the second it really is situational for me, since i don't need any particular to fill out my role. The ones i normally choose between is: Now i take this, if the other team is very squishy and/or fast, to more easily chase them, though it is very rare i take this, since you already have the speed boost from Exhaust Size 64 I take this, if they have for example a so my team doesn't have to switch their summoner spells i take this if they have a very strong life steal team, and especially if they have a i take this, if they have a very CC heavy team, or if my team is especially squishy. I take this, if there is no need for any of the others mentioned above, since it is useful against all teamcomps, but you can play without it.

That was my Warwick guide, hope it helped, and i will update this, as often as i can/need to. And let me know in the comments what you thought, if you noticed some grammatical errors or any other form of constructive criticism.