I don't like the void staff on a singed. There are other items like lichbane that I think suit his playstyle more. Lichbane offers bonus speed as well and speed is singed's best friend. Also, I'd go with a 9/0/21 build as well, but I think the 15% spell pen would be better than 10AP, so I'd go with that as well.

Thank you for the advice

mh for AP singed i would prefer a 9/0/21 or 10/0/20 build with ignite/ghost.

Also 180 AP for AP build is way too low.

Why start with a Regrowth Pendant ? Take a Sapphire Crystal and 2 healtpots and try to get catalysator as fast as possible (=> Better then regrowth pendant). If you do well you can easily get 2x ROA with Singed. You'll get more HP lategame as with Warmogs. And if not, buy a rilays, its slow works great with singed.

And seriously, you need at least 1 point in Mega Adhesive with lvl 4 or 5 :<.