These players arbitrarily manipulate matches, collude with each other and kill one another to gain a large number of points in a short period of time. I think this kind of behavior is no different from what happened during the previous Mirage2000C-S4 event.
On the way, a player joined in and asked, “Are you guys doing PVP?” They admitted it outright. The term “hu shua” refers to collaborating with the opposing side and killing each other (to exploit the game mechanics).