I'm looking for this one live-action/animated TV series that I watched in the early to mid 2010's (around that period of time at least).
It featured this group of three (or four) teenagers who would fight people who turned into animated monsters (I think Netflix picked up the series at one point).
The main cast consisted of two boys (I DO know one of them was named Iko or something, and I do remember a period in which Iko wasn't in the show for a bit because his actor was unavailable [they explained it in-story with how he went on vacation and show us this postcard, which I thought was funny]) and one girl. There might've been a third boy, but my memory's a little fuzzy.
Anyway, I also remember that almost all the teenaged protagonists turned into monsters themselves over the course of the series that the others had to fight, except one of them.
I've ruled out series like The Troop, Monster Warriors & ReBoot: The Guardian Code.