As a Shyvana main, I've thought and tested this build over and over, and have LOVED this build ever since I put it together. Mid/Late game team fights are a breeze with a team that works well together and Shyvana in the middle of the fight, and this is why...

Focusing on dragon form in the middle of a teamfight, anyone basic attacking you is taking damage from Thornmail, her burnout, burnout trail, and cinderhulk is doing damage to everyone around you, her Twin Bight is (if you go with the hydra) setting off hydra's passive twice to everyone in front of her (plus the actiive) or setting frozen mallet's passive off to many people if you chose it, her Flame Breath is marking everyone in front of her that works perfectly with the B.O.R.K. passive. and the runes plus her passive means 67 armor and magic resist in dragon form at level 18.

This is all based on Shyvana's late game, since her early game isn't THAT great compared to other junglers in this meta no matter what you build.

Pros

-Great wave/jungle clear
-GREAT team fights
-Nice split pushing due to her Q and W
-Insane late game potential

Cons

-No great CC, only B.O.R.K., Stalker's, and Frozen mallet if you go with it
-Not a great early game
-Doesn't fair too well in 1v1s unless fed or has sated

Start smite Gromp, then Blue, Wolves, and smiting red to get health back, then skuttle, If no problems occur, with the life steal runes and smiting red, you should be able to make an early gank.