i would use erase soul

First off, there are no souls in BN6, they're crosses, Bass, especially GS would near impossible with souls, considering their short term effects. Double area grab and slash cross is pretty effective on most enemies though, as long as you can move around a fair bit and still do damage.

for Souls,,i'll use Colonel soul because its v-cut is a long ranger melee strike.

for cross,,i'll use Charge cross...

DONE!

i'd use charge cross cuz' when bass uses his busters let your charge shot go and voala!basses busters are dissrupted