Vayne is a great melle dps, perfect for taking down tanky dps or tanks, the way I build her requires you to know how to use the stun, or to stay back in team fights and be smart, but it is well worth it :)

The runes are somewhat interchangeable, I would leave the Armor Pen though as this build does not pickup any armor pen through items. Blue can be changed to mage resist if you have problems with AP characters.

The items in this build are focused on increasing your damage through critical, and your tumble damage boost. While also adding on a lot of movement speed so you can easily get away. The movement speed is also very helpful when dodging while using your ulti(explained later.)

Tumble gives you an extra 75% damage, which is then multiplied by 2 via critical. For example instead of doing 100 damage you will now do 350, as both the critical multiplier and the bonus damage from the tumble stack. This all is added onto your sheen or trinity force bonus, adding more bonus damage, all in one hit. The cooldown upon doing this at 18 is only 2 seconds also, very quick damage.

Flash

Flash is useful to help you quickly jump out of range of your enemies if you decide you dont want to fight, if you get CC'd with this build you are done for, unless you can flash.

Ghost

Ghost is one of the best spells for vayne as you can use it with your ulti at level 6 to surprise people. It works really well early on as you get your boots late, but it helps you stay with your enemy and dps them down while they attempt to run. It is also very helpful to help you position to use your stun.

Final Hour to escape

When you're in a bad position and you're attempting to run you can use Final Hour to help out. If you're near any bushes it works really well.

First you need to head towards the bush, ulti and then roll, turning you invisible, then with the extra movement speed from ghost, or your items, your invisible state will last long enough to the point where you can get out or range, or escape enemies.

Positioning with Final Hour

When attempting a gank, Final hour with the invisible aspect can also help you line up enemies for a stun. Use final hour while in the bush, dive out and quickly position yourself either A) to stun the enemy, or B) to push him towards your teammate. If he's not near a wall a stun isn't possible, but if you push him towards your teammate, it helps your teammate get in range to use his Crowd control.

Basically this build requires a lot of movement from the user, but is very powerful against everyone. The attack speed stacks up silver bolt damage quickly, while the spells help escape, or chase down enemies.