Runaan's+Lifesteal is game breaking past 25 minutes and needs to be changed.
GW is supposed to be in place to reduce healing, but if an ADC has Runaan's it merely cancels the bonus healing it provides via the bolts. The ADC still gets nearly full lifesteal without anything you can do to mitigate it further outside of gimping yourself by building Thornmail for some absurd reason, which only even helps if the ADC is focusing you.
#Ranged should not be able to apply lifesteal via AoE. At all. **This is why Ravenous Hydra is melee only. **
As an added bonus, Warlord's Bloodlust is taken almost universally now on ADCs since the Fervor change, making the lifesteal extremely oppressive to face without any way to work around it significantly enough.
#Mages with burst AoE sustain (WotA when strong) are bad for game health but ADCs with it are okay when they're also doing it 1+ times a second without any penalty for range differences or hitting minions?
