The first idea was to create an Eldritsch Zac, like formless flesh, pulsating and twitching...
That didnt quite work though for the following reasons:
Eldritsch and otherworldly stuff is pretty much covered by the Void in LoL and all void based skins are purple.
Sadly, Zac already has a purple skin, which is why I didnt want to go for a Void Zac skin.
After a few more thoughts I came up with this version.
Cosmic Zac is inspired by Algalon from WoW and Aurelion Sol (LoL).
Also: Here's the link to the LoL Forum in case you'd like to support it there: