Kha'Zix evolved Q bug.

So, I was playing kha zix recently and evolved my Q at lvl 16 while having Black Clever, Ravenous Hydra, BF Sword, Last whisper and Boots of mobility in my inventory. I read the tooltip and it said the isolated Q should deal "base damage (+ somewhere near 660) damage. But I noticed that it dealt merely 321 damage on an isolated enemy ADC (Graves) and a Sona Supp. Sorry I couldn't screenshot it back then, just wanted to share and find out if anyone else had a similar problem.