Overview:
Skaarf is one of the only mages that has potential for a WP build that can actually work because of two things, his perk and his base stats. For example compare almost every mage(Except Reza and Reim and maybe a few others) with Skaarf, the other mages start with 10 Weapon Power and don’t get anymore, meanwhile Skaarf starts with 80 Weapon Power and finishes at level 12 with 154 Weapon Power which is nearly as high as some bruisers. The more important potential is his perk Fan the Flames(more on it later) and this gives Skaarf the chance to build WP viably.
Passive:
Fan the Flames it the key to WP Skaarf’s kit, and it lets Skaarf’s damage be on par with traditionally Weapon Power heroes. Fan the Flames makes 2% of the enemy’s max health as crystal damage on a basic attack. This gives Skaarf a huge advantage early game when you can’t build enough defense to reliably stop Skaarf’s damage and still works well in the late game. Fan the Flames can also crit dealing 4% of the enemy’s max health as crystal damage which is important for Skaarf’s WP build. Overall Fan the Flames is the only reason Skaarf’s weapon build could ever work.
Skills:
Spitfire: This is your main option to getting Fan the Flames on enemies so I recommend getting it first and overdriving it as soon as possible(Level 8).
Goop: Goop helps apply Fan the Flames on everyone in team fights so I recommend getting it second and overdriving it at level 11.
Dragon Breath
Doesn’t matter. Moving on.
Items
Core: Spellsword, Attack Speed(Tornado Trigger or Breaking Point), Crit(Tyrant’s Monocle or Tornado Trigger), and Defense.
Try landing a Fireball on a Ringo, Dragon bout to get his ass beat by Ringo, Gwen, and Kinetic. His weapon path used to work nicely but like Niv said, its a little outdated for 3.0 and above.
I have to admit that i play Wp skaarf when cas-ing with my pals or in Br. Crit path is most effective imo
Skaarf has a higher damage output than any of those heroes early game(except possibly Kinetic), also Weapon Skaarf should be building 2 or 3 defense items.
I tried out wp skaarf here.
I feel it’s something everyone should play at some point in their life, if only in a 3/5 man queue to prevent tilting soloQ teammates. The crit animation is one of the best in the game; such a shame most people live their lives without ever seeing it. 
Unfortunately it isn’t viable, skaarf is a long range mage, getting in close for basic attacks is not his play style. It does make laning phase remarkably easy though, the two games I’ve played him we snowballed from laning phase because of how hard he hits early game.
I refuse to play WP Skaarf what’s the animation? Can I find out in practice?
It’s not that amusing… why is it so great?
You know that got me thinking. Why would semc ever add crit animations to there heroes that arent meant to have wp.
I think someone had said Skaarf was supposed to have a WP path and had ratios for it but they scrapped it.
He isnt the only exemption though. Like ALL the heroes have a crit animatio for heroes that shouldnt even go wp like celeste. Dont know if i should take this as “wow the details!” Or “boo, work on more important issues”
I wonder if they put those there for the possibility of massive shifts in meta or playstyle so they didn’t have to add them later if they needed to?
I dunno, I just love it so much. Skaarf is SO cute. 