IMO Statikk Shiv is more of a conditional item. That "Greaves, PD, BT, IE" build is pretty much core items on Vayne (and basically, almost all ADCs). The last two items are situational. LW for armored enemies, Shiv for mobility and AS, Warmog's for toughness.
I do sometimes build Shiv and PD on Vayne. As long some conditions are met, I get them together.
True, I think I should start getting it more as a situational item rather then blindly go for the defensive item. I haven't been using LW much lately since it's all health stacking and Silver Bolts take good care of that.
Your second attack item is situational as well... Sometimes it's good to get a Blade of the ruined king instead of a IE or BT. I'm the fail ADC that doesn't even get a Defensive item but then once build is complete I slaughter things lmao.
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