I've been rocked by a good AP Tristana bot lane a few months ago. She rushed a DFG (followed by Rabadon's and Void Staff). and would sit in the speed shrine ignoring farm as I last hit creep. Then after the inevitable pushing, she'd Rocket Jump over bot wall, DFG mid flight, Explosive Shot + Buster Shot. I died instantly every time despite Odyn's Veil, Merc Treads and Phage in an attempt to tank the burst and retaliate on her cooldowns. She wait for cooldowns in the bot speed shrine for me to come back to lane and then would kill me again and again and would make use of an easy cap after. The two ganks I received ended immediately after she'd jump away. It wasn't until laaate game and two more items before I could do anything that resembled retaliation as teammates flamed me.
Needless to say, I was embarrassed after that match.