The power of nothingness and blessings
Kazuki was like Jesus with Mark Sein, while Soushi devours everything on sight.
Both of them had already been completely assimilated by festum in Dead Aggressor, since then they can also assimilate their enemies, with the blessings of the recently awaken island core Minashiro Orihime, they not only can pilot the damned Salvator model machine that has been sealed from previous series, but also have an insane mech regenerative ability and power output.
WACOCA: People, Life, Style.