Hmm... maybe I'm not playing Skarner right then... I always go Hybrid Bruiser build with him, focusing on AS/CDR and hybrid items as well as a little tanky.
For example, one build I like is first I'll go cloth and 5 pots, then philo stone -> mercs -> stinger -> wits -> shurelya's -> GA -> sheen -> trin -> nashor's
I've found this to be a very solid build as it gives him around 2.75k health, 168 armor, 150 MR, and plenty of damage, CDR, and AS to synergize with him abilities. Not to mention the GA greatly helps if you're getting focused, which, because of my ult, I find happening quite often.