Quote Originally Posted by Ryllharu
Everyone else is just lollygagging around. If no one else will take charge, Setsuna might as well. At least he knows what he wants.
About this line.

When Ian talked about his colleagues having a reason to fight, Tieria was the only meister not mentioned. To date, we still haven't heard any backstory about him. We kind of accepted that he's in CB because he can link up with Veda. (and mostly because he's the one who questions others for being in CB). Regardless of his initial purpose, I dare say he now inherited his will to fight from Lockon.

The OP (life pods) hints that his kind were probably created for some purpose in Aeolia Schenberg's plan, while the ED (shooting the mirror) looks like he'll sacrifice himself to take down his fellow androids once and for all.