Just looking for advice on Vayne. I'm getting fairly good with her.
A few questions though. . .
Would Armor Pen marks be better than flat ad marks because you get more dmg on the opponent adc if they have armor seals or something?
Is Youmuu's Ghostblade 
that good on her? Like I see all the pro's using it, but I'm just not sure as to why. Do you need to master her for this or something?
Just tips and tricks in general please.
Build Bork first. Max Q early for 2 second CD. Don't fight early unless you have a clear advantage. BUT----- Don't take free harass in lane, if they don't have CC up, make sure to Q and hit them.
Master farming, because its the difference between being a God midgame, or just lategame.
I use attack speed runes(and a few AD marks) for early CS'ing under tower. Thats just my preference though, because Vayne doesn't have that many good matchups.
When you hit lvl 6, you should be able to fight most ADC's so long as your supp is competent. I don't recommend going aggro, but if they screw up, you can usually come out ahead.
I don't buy ghostblade because usually I'm around the AS cap and I prefer more damage or a situational defensive item. (I'm not saying Ghostblade isn't awesome on her), but I usually just buy Bork/Shiv/IE/Last Whisper/BT/ defensive item
Vayne can be tedious to play but can be very strong if you can use her right. She is a Tank melter that can wreck havoc the longer the game goes on.
i Max W first for the true damage.
I build bilgewater cutlass for some AD then buy statick shiv then finish off the BOTRK then buy bezerkers greaves with furor to help chase your foes down on top of vaynes passive. phantom dancer, infinity edge, then guardian angel.
vayne thrives on attack speed so its always good to have more attack speed early to proc silver bolts faster, it also makes farming easier and clearing waves much faster
Max W then Q then E and up your ult at 6 11 and 16.
Importance of vaynes abilities.
Q- Tumble can be used to dodge skill shots or help you escape trouble it also makes your next basic attack more powerful based on your total AD
W- silver bolts this is your main skill and also makes up alot of vaynes damage. procing this will annihilate your foes the later the game goes on. Deals % of max HP in true damage.
E- Condemn great for pushing foes around. knocks enemies back (including neutral mobs and minions) and if your target hits a wall/turret/inhib will stun them for a brief time, also adds a stack of silver bolts.
R- vaynes ult gives her alot of power, granting bonus AD and doubles her passive and everytime you use your Q you go invisible for 1 second use this to your advantage to throw off your foes.
vayne may seem difficult to play at first but one you get the hang of her you will be carrying matches easily.
Also dont copy what the pros do. i use this build style and it works for me everytime. its what works for them but different items may work better for you.
Use Q to dodge skill shots and you can use Q to cs or poke enemy adc. In all honesty check enemy support. If they have a non healer support then you can take the bonus damage proc from Q and shoot it at adc but if they have sustain most of the time just use that to farm minions.
Vayne in general is a avoid a fight type champion but you do need to help your team help you. If your jungler wants to gank and enemy has no sustain then it would be nice that you poked them down a little with your Q or if you have a Blitzcrank support then it would be nice for him to hook a low hp target to secure the kill.
Watch hi im gosu he is the vayne god
kk im piglet's father so ill answer with my best advice.
GUYS GUYS GUYS IM A VEYNE MAIN AND DOUBLELIFTS SON AND I HAVE TO SAY THAT IM THE BEST VAYNE IN THE WHOLE UNIVERSE SO IF U THINK U BETTER THEN M,E COME AT ME BRO I HAVE 3 CHALLENGER ACCOUNTS 2 IN KOREA AND 1 IN NA
AS ≥ AD > Arm.Pen. Marks. I don't think that ADCs have taken Arm.Pen marks since S3. Your true damage also makes Armor pen slightly less of a priority.
I personally don't like it, but it provides CDR where you get usually get none elsewhere. Which is less generally useful on Vayne, anyways. They use it for the active, in combination with BotRK and your ultimate, you get tons of damage and chase/kite power. If it takes more than 6 seconds to kill someone as Vayne, you're either dead or about to be.
Some simpler tips if you're just starting with her..
Firstly youmous is used to magnify all her strengths but ONLY if you can use the active well, if you're bad with actives don't buy it.
Never Q in a straight line unless chasing, she's one of the few adcs that can freely dodge skills hits (rather than running from them) a successful dodge can easily win a trade.
Use tumble and condemn to attack reset for sudden silver bolt proc bursts
Don't worry about arp runes on vayne AS procs more bolts and AD makes farming easier
ult-tumble-flash can cover enormous distance while invisible, do not underestimate the usefulness of that time when ganking/juking/setting up condemn.
Use red boot upgrade, vayne excels at dealing with bruisers and tanks, these will make you untouchable.
If you have a gank comin don't warn your opponent by ulting in the open, move to the bush first to get invis and try to maneuver behind them to condemn toward jungler.
If they are turret hugging and you are safe from jungler go ahead and condemn them into their turret or even just away when they try to last hit to assert dominance lol.
