I'm still practicing and perfecting this build but I do strongly believe that this could be the best rune for warwick due to him being able to double as an assassin with his blood hunt, and a team fighter with his large health pool.

Omnistone:
You should take the time to learn how Omnistone works to get the most out of this build. If you do not learn omnistone manipulation then this build is pretty useless. You need to know how and when to use each rune in the game to make the most out of this build.

Here is the link to the omnistone page on the league wiki if my explanation sucks.

To put it simply, omnistone will give you the best rune for the situation. The first Keystone granted will last for 3 minutes and every keystone thereafter lasts 40 seconds. Furthermore, there are many conditions that can be manipulated to give you a desired rune.

Here is an extract from the wiki on how smart keystone selection works: "Smart" selection takes place before Omnistone rolls its table of Keystones; if an ideal situation is found it will have an 8 - 15% increased chance to roll the relevant Keystone.[1] If you would otherwise not roll a relevant Keystone due to it being removed from the table, Omnistone Omnistone will refill its table of Keystones, and grant you the relevant Keystone.

If you want to stack dark harvest (which I strongly do suggest) and build more adaptive damage, you will want to be hunting low health targets with your blood hunt and play almost assassin like. Dark harvest works similarly but also in a unique way. First of all, you will be granted dark harvest around a low health champion. Secondly, dark harvest stacks remain even when you are given a new keystone, so you can continue to abuse this with well timed jungle rotations and good laners.

Thats just one example of abusing keystones, again I strongly suggest you look on the wiki at the keystone conditions so that you can figure out what keystones you will be getting when and where.

Runes:
You can exchange flashtraption for boots and biscuit for future market if you want to conserve gold. You could also take boots if you know you can snowball. Absolutely do not take dematerialiser because it is bloody dreadful for junglers. Stopwatch is useless because you will already have the sustain and won't get the gold preservation when buying zhonya's.

If you saw this guide before this edit you will note that I have swapped velocity for cosmic insight as I dont believe it is necessary. You already have lots of movement and your ult makes you impermeable from cc. Also building ability haste is fun and allows you to spam q more often so that shouild always be a jolly.

As for the second tree I like to use precision however you can exchange this for domination with sudden impact and ravenous hunter, or you could use sorcery and go water walking with celerity for easier river ganks and rotations. Resolve doesn't work from my experience but if you want to experiment, go ahead.

This is my first build so forgive me if I made some rookie mistakes; if you have any suggestions or advise, please let me know.