Vayne ability revamp idea
(Q) Tumble: Vayne tumbles in target direction, her next attack will have 10/20/30/40/50% of it's damage converted into true damage, and will also knockback her target slightly (Similar to Graves attack against minions and monsters). The knockback can't knock enemies outside of her attack range.
(W) Silver Bolts: Vayne's basic attacks and Condemn poisons her enemies' blood with silver. Every attacks apply a stack of Silver Bolts to her targets, when the target reaches 3 stacks, every attack deal 2/2.5/3/3.5/4% of the enemies' health in true damage, each stacks beyond the third increases this damage by 0.25% and can stack infinitely.
(E) Condemn: Vayne pulls out her heavy crossbow and unloads a full clip of bolts toward her target. Range: 700, but each bolt travels 900 range she fires 4/5/6/7/8 bolts over a one second duration. Each of these bolts deal 10/15/20/25/30 damage + 30% of her AD, and apply a stack of Silver Bolts. The spell is a point-and-click skillshot, you target an enemy and Vayne fires toward them in a straight line. Each bolt can be dodged and blocked by minions, but they will follow their target's current position when fired. Vayne can still move and use Tumble when firing. This ability will naturally be more effective against tanks that are usually slower and have a larger hitbox. 18 sec CD but auto-attacks reduce the CD by 1 second.
(R) Final Hour: Grants Vayne invisibility for a few seconds when used, and also instantly refreshes the CD on her Condemn, she can still use Tumble while invisible. Kills will allow Vayne to reactivate Final Hour if used within a 10 second window of the first activation (extended by 5 seconds for each kills)
I think this kit would solidify her enditity as a tank-buster instead of a short-range hypercarry. The knockback on her Tumble would give her decent peel against melee champions. The stacking mechanic on her new W would reduce her burst, but increase her sustained damage against the same target. Her new condemn would give her damage and utility while outside of her auto-attack range while also offering combo potential since it applies and proc Silver Bolts on each hit. The new condemn spray would be very effective against tanks since they have a bigger hitbox and are usualy slower. Her new ult would give her some of her ''1v5'' potential with its reset mechanic, and give her an opportunistic mechanic to use when she wants to commit to a kill.
All-in-All, this new kit would trade some power away from her auto-attacks in favor of more versatibility and outplay potential, giving more tools for Vayne to use. It would also make her gameplay less binary and less feast-or-famine.