Alright, time for me to explain how Vayne works!
So, big thing to go over is his attacks and abilities, so I'll just slot them here in the beginning:
So, How does Conqueror's Power Work? It's a three stack max buff that his entire kit contributes to, with the exception of his AA, which only preserves it.
Basically, he will start the battle with one stack, and when he gets to Three, usually with one use of Mach Wave at the start, he will transform all his abilities into + versions. Contrary to how ability changes work, these are NOT improved in any way, they merely no longer provide aditional stacks of [Conqueror's Power].
Once maxed, and all his moves turn into + versions, ALL of Vayne's turns will be free until [Conqueror's Power III] runs out. It is a two turn buff, which means you get two free turns, with
Zero Action Delay, meaning they happen in a row. Since they have no action delay, you receive a Third turn that
Isn't Free, right after the first two. That one is where all the attacks turn back from + to normal.
So, to summarize, once he receives his full three stacks of [Conqueror's Power], he no longer gets stacks and his next two turns become free and happen continuously.
His ability set, which looked sparse and weak, with the exception of Force of Will, changes dramatically under this context. Not only does his free turns allow for enemies to recover from break faster and be broken faster, he can more easily pepper his Hp+, Pummel, into his routine, allowing for effective and quick bouts of damage.
What's more, what used to be at most 20K damage from these regular attacks rise into 30K from a new buff during free turns, as he now restores 20% of his Max Brv per action when under the effects of [Conqueror's Power III]. So he can do at least 55K of damage during his free turn combo without using a single action!
And that's not counting the ACTUAL strategy in using him!
Since his EX+ both gives him full stacks, as well as restore a use each to Both his abilities, careful management of his ability uses can extend his longevity to rediculous levels while maintaining a powerful offensive!
For example, saving a use of Mach Wave until after his free turns makes it so any one use of any attack he has, even his Hp+, will provide him the last stack needed to trigger his free turns.
Or, you carefully make use of abilities during free turns to trigger his EX on his last action, guaranteeing he goes on his free turns the turn he gets after!
By making full use of his kit, he is a devestating attacker, capable of destroying enemies in concert with aura buffers to extend their effects on him through his Free turns, such as Aeriths Atk and overflow buff, Yuri's 20% Max Brv based Regen, Lilisette's all Crits aura buff, the list goes on.
He's awesome, and I hope you all make the most of him!
Main Weakness: he doesn't shave very well since he does all his damage in crits, and buffs run out on him much quicker due to all the free turns. Watch out for that and try not to pair him with characters that are nothing without their buffs. Penelo, for example, puts out a bunch of buffs, but all her best effects are Aura based, so she isn't much of an issue!
Edit: also, he is very bad during Summons due to his free turns eating up the summon turns, though that is more easily rectified by using a powerful Friend unit to replace him with, like Aranea or Setzer, before or during the summon.
Bring out a Friend Aranea, and get her to use Highwind before starting the summon so that her consecutive turn doesn't eat up the summon, and use her to skip the enemy's turn forward. That way, when Vayne comes back, he'll ALWAYS do crits and can take full advantage of her debuff, dealing IMMENSE damage, and possibly delaying a boss or bosses all the way to the back!
In duo's, his single target focus loses some flair to more AoE focused units, but his Party Aura and his unique Unbreak mechanics, especially on his EX+, keep him relevant in double boss content!
