No video, but really, it is a matter of power. My Iris and Alissa under their skills and with support of Shuuka's can keep health of a team good enough while my Mehlis and Thetis melt liches. Barbie-jii and Zola provide additional fire if liches hobble into their range, but before then they just chill out) All CCmax, of course. I think Claudia with her skill could be even better choice as MR tank, but if Thetis works, why bother with replaces?
Ah, I also place Thetis first and so force liches to target different girls instead of ganging up on poor valkyre, so there's also that aspect)