AP/AD Warwick Toplane
The AP/AD Warwick hybrid is great fun in the toplane, a refreshing change rather than the normal AD Warwick jungle, he focuses much on the on-hit effects of items such as Blade of the Ruined King, Nashors Tooth, Lich Bane, Wits End. The strength is in the essential part of Warwicks ultimate, where he applies on-hit effects 5 times, thats why the items such as the Blade of the Ruined King, Wits End, Nashors Tooth, the Black Cleaver fit in so well, items which damage is superb but the damage is hard to apply, this makes it easy, and devestating, overall fun build.

The AP/AD Warwick is a fun build, giving you sufficient defense if needed, great sustain both early and late, high damage output, being able to almost 1 shot the carrys in the end game. All over the AD/AP Warwick is great fun, however take caution since you can be weak to AP Champions in the top lane due to the rune build being set up for facing AD Champions up top. An easy solve to this can be: if you have a rune page to spare set up a page for facing off against an AP Champion in the top lane (will only work in draft:normal and ranked). The laning is great, the Dorans Blade makes it very easy to last hit and the sustain is great in the early levels, the harras is also quite nice. The Ultimate is what the build is most focused on for damage output early, the items have on-hit effects which will add on to the damage already derived from your ultimate.

This could be viable in ranked play but i recommend not playing ranked untill you have praciced sufficiently in normal mode so you know what to expect in lane, and how you personally face of against other champions in the lane. So if you decide to play Warwick AP/AD in ranked and end up losing, do not blame me for the build, take your time to practice this build in normal and make any small alterations you feel fit your playstyle better.

The Pros

Farming is a Breeze

You have great sustain

Strong early and late

Huge damage output

The Cons

Vulnerable without Ultimate

Susceptible to ganks early

Not as much ability to escape as other Top Lane Champions

If caught late game cannot do so much to get out

Use your Team!!!
The perfect thing about the AP/AD Warwick late game is that the ultimate is basically a 2 second stun with insane dmg and long range, use this to take out that pesky fed enemny Jinx or Caitlyn late game, securing you that win you so much deserve. Remeber to communicate with your team so they know what you are planning to do before you actually do it, otherwise you might end up going in alone and you die before your team has the time to react.

Farm Away Mr Grey
The Farming on the AP/AD Warwick is a breeze, after you start getting 1 or 2 items the attack speed will be high and so will be the damage, even early game the AP/AD Warwick has great damage output due to the passive and the first item Dorans Blade, if you care to farm later you can kill anything without reason (dont try to solo Baron please) without even taking damage due to the amazing Warwick selfheal that is amplified by the AD/AP build, so have a great time farming away at that 400 cs while your team is raging at you for never joining the team fights.

For the Maximum Damage!
For the maximum damage with the AP/AD Warwick build do as follow: Find your target, press R on your target, chill for 1.8 seconds, then finish of with Q and a few auto attacks if needed, the damage will be quite impressive, so make sure everybody is prepared for it, and that you yourself are prepared. However if you are ever stuck in a situation without your ulti and facing off 1v1 against somebody, this can also be a skill combo: Use W and Q whenever you can, if they try to run away you always have your E, so happy hunting!
and remember

"It's more fun when they run"