I really like this build, other builds have been putting armor and other stuff that I don't think Vayne needs... She just needs more damage but a GA for some survival :)

Vayne does not need mana regen, you can spam any keys you want and you still have mana to burn. I like a fast vayne so i got 2 movement Quintessence or you could get 2 more armor penetration.

I take critical to really give power to a early infinity edge. I do get a bit of mana because not getting mana with the runes but the movement speed is what i wanted in utilities. Her passive can be really cool with a fast vayne.

I dont really like the doran's blade and if your really spamming hard core, the mama regen doesnt get wasted. I really like the extra gold and health lets me stay in lane well enough (I dont mid.... EVER). With the masteries, a early early infinity edge gives a lot of damage. Zeel gets my speed up. OK you can get the GA if your being focaused in team fighting (like they should) this will allow you to unload some damage and than not die, flash and be able to run faster than anything else ( all the movement speed really allows you to do this). After that finish dancers and more ad based on needs. Blood thruster health steal if GD isnt doing enough or not killing squishies fast enough? Get BC.

I rather get Silver Bolts than tumble because of all the true damage... (I might not be 100% of levels but you get the idea). I think poking with bolts does a good job, if you get 3 hit or if you get them to run after 2. This lets you farm or get kills.

Flash saves me for early and with GA, ghost doesn't do enough. I take teleport for coming back after ganking mid at level 6+ or saving towers late game to help farm (you should be a good farmer)

Dont get focused and this build is really good mid to late game unless you have a great early game. Gank mid after 6+. It really helps vayn's early game with a few kills or at least assist. Dont ever stop moving, you will have so much movement speed so be moving out of the way or chasing.