Quest says to use F (Grab) against Lunatic Daewang, then use Z (Power Slam) to attack Daewang's underlings.
I've been doing this over & over again countless times now and the quest won't get completed. I'm aware that I have to stun Daewang in some way to follow up with the grab, I've tried doing:
1 > F > Z
TAB > F > F > Z
4 > F > Z
2 > F > Z
Z > F > Z
None of these grab combos seem to be working for me, am I missing something?