I'm ok with Zeno's being the big bad at the end of 6.0.

We've already had our feel of sympathetic villains with emet Selch and Niddhog and had our power hungry one with Thordan.

I like Zeno's being the deranged crazy one that gives no cares cause he just wants his battle and he kinda has that serial killer vibe to him, which makes for a good villain choice cause he's a must stop villain, can't let this guy carry on.