I'm wondering cuz being a giant dragon flying over walls to gank people sounds like a lot of fun. Plus he's a mage which I like.
is my main for jungle, and I'm wondering if 
is decent as a secondary jungler.
He was never bad
Buuuuuuuut
His learning curve and playstyle is not suited for everyone.
Asol as a jungler is just wasted potential when he has great laning. You'll have a far easier time roaming from mid lane with superior XP and CS than you will as a jungler.
Tried it. Got to roughtly 250ish mastery points playing him mostly Jungle/Top. It's situational but it works.
It is a risky pick during a carry top + tank jungle meta. You deny your team a potential tank in the jungle. If your toplaner also goes squishy, which is likely, you will be under pressure to snowball the game early before the enemy's frontline becomes too strong for you to punch through. Luckily, Asol is extremely good at pressuring bot thanks to his ability bypass ward spots with his E. Simply wait for the enemy support to commit to a play, and fly into the lane. Turn on W and pick up some easy kills. The same can be applied to mid/top lane but Bot gives you the highest bang for your buck. After that, proceed to take turrets and dragons and hopefully gain a big enough lead that the enemy team never gets to outscale.
In a carry jungle + tank top meta Jungle sol is phenomenal. You still clear well and gank like a beast, but you will consistnely have frontline to play around in late game teamfights. It takes a lot of pressure off of you to snowball the game early, and you begin to be able to make use of his strong late game teamfighting potential.
