Really loving the new Zz'rot
The fact that so many of the new items are for pretty much stacking health, combined with the fact that zz'rot scales off of health now, while giving you awesome resists, lets you be deceptively tanky with only Zz'rot as your resist item.
My standard Singed build has changed a bit.
Old build: Rylais > Boots > Liandry > zz'rot > thornmail/deadmans > Banshee Veil.
New Build I've been trying: Rylais > Boots > liandry > Zz'rot > ROA > Warmogs.
Of course, most straight tanks still need actual resist items like randuins, but for bruiser and juggernaut types, it's pretty fucking awesome and underused in my opinion. So much synergy with champions who build a lot of health and less resists.