The reason why Vayne isn't doing hot currently.
Reason 1:
Why would you ever need a tankbuster ADC - When pretty much any and every ADC nowadays is a tankbuster post 3 items thanks to the massive ammount of damage enhancement from out of game stats?
Reason 2:
AoE/Control mages are tankier than ever, generally as tanky as bruisers at times while still retaining their signature burst damage potential thanks to derperlords and if that didn't make things worse, they can also spamm spells, including cc at a rate never before seen since cdr is literally tacked on to just about every of their core item in the game by nowadays, or at least, on more of them than it's not.
Reason 3:
Damage has been raised massively across the board, meaning that her true damage simply isn't as impactful, especially against teams that don't have alot of tanks.
Reason 4:
Her counters are doing hot.
There are probably more reasons but these are some that I could think of.
All that said... Does that mean that Vayne needs to get buffed to meet the meta standards? Honestly, I don't feel so, she's still the slipperiest ADC out there and one of if not the games strongest duelist when fully built, also she still retains her signature as a choice pick vs teams that double or tripple tank. She doesn't need to be effective against all setups.
Bring on the hate. [slayer-pantheon-popcorn]
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