Let us hunt those who have fallen to darkness…
<Note – After all the Kraken Slayer buffs, I recommand going Kraken Slayer First item and skip Blade of the Ruined King However, Blade of the Ruined King is not a bad item and a lot of Vayne players still start with it. It also depends on matchup (Versus heavy poke/Tanky team) Judge for yourself >
Vayne is reasonably weak early game. She can deal quite a lot of damage once she gets a few levels on her Silver Bolts (W) combine with her Rune Press the Attack, but she will struggle vs strong early game champions such as Draven and Lucian. It will also depend on your support how your playstyle should be. If you are playing with a champion such as Pyke, Blitzcrank, Thresh, they should make them do the first move, then you follow up on it. If you are playing with an Enchanter support such as Lulu, Janna, Yuumi, Soraka, you should be the one making the first move.
The early game depends on who you are against in lane. You will always want to build towards Blade of the Ruined King but the build path will change. If you are against a heavy poke lane such as Caitlyn, Ezreal, Varus, Lux, Vel’Koz you need to build Vampiric Scepter as soon as possible. This will gain access to regain your health. Your rune setup will have life steal also but it wont be enough vs a heavy poke lane. If you are vs a catcher such as Thresh, Blitzcrank, Pyke the best choice will be Berserker’s Greaves to have a higher chance to dodge their core ability to setup a kill, otherwise start with Recurve Bow.
A lot of the games depends on which champion you are versus. If you are versus champion such as Draven or Tristana you will find that they push a lot more than the usual ADCs, so you have to adept your playstyle and auto attack the minions more to make sure they don’t die by the tower once you are pushed in. Thanks to Vayne‘s Condemn you will have an easy time setting up ganks for your jungler or hooks for your support.
On Summoners Rift, there are two sides. Red and Blue, as you have probably figured out at this point. But they have actually advantages and disadvantages. The Red side has it a lot easier on the bot lane because of the big mountain that is blocking by the first tier tower. Therefore, you can freeze the wave right before the first tier tower to safely farm without worrying about ganks. You can also easier do a Flash Condemn play towards the mountain to set up a kill. They also have a easier time to get Dragon because of the paths that leads there.
If you are on the Blue side, you have to worry about the “Tri-Bush” and the river, but you will have access to red buff from the bot lane and Baron later into the game.