I may be a nonexistent elo (ex-Gold, floating between Silver 3-5 ATM) Shyvana main...

...but I have one tip for all remaining Shyvana players. Our dragon girl is now falling out of popularity (which is good, we wanna be unique), but I just wanna say this for those still loyal to her.

Please, please build DMP/Randuin's/Banshee's/SV as a second item. I see people going BotRK/other offensive item immediately after Devourer/Warrior too often. Shyvana is not Yi, Jax or Xin, she's a heavy fighter (like Darius). By going for a second offensive item immediately after your first you're denying yourself the valuable resists that go with your passive (and need some HP to be of use) and gimping your team (because with a tank item second you don't get bursted immediately and are a threat both damage-wise and tank-wise).

Titanic Hydra is not bad as a second item, but I still find DMP (if they have a lot of AP, Banshee's) to be superior, since it makes me a bigger threat and makes me sit in the middle of their team longer.

(if you're going Cinderhulk then feel free to get an offensive item second, though I highly recommend Titanic Hydra over anything else, since it scales like a beast dragon with any Shyvana build).

PS: Frozen Mallet is decent as a final item, just because it's hated doesn't mean it doesn't function well.