with this build stacking up your combo counter will be easy, and keeping your combo counter will be even easier
[Killing Blow] + [Organ Shatter] give more damage and recue heavy attack wind up speed, letting you throw the [Xoris] quickly, [Swift Momentum] can be used to make the throw speed even faster
if thro speed is not a concern you can swap out these mods for whatever you want

[Focus Energy] + [Reflex Coil] will reduce the amount of combo counter you use by 90% this essentially gives you 10X efficiency when expanding the [Xoris]. letting you explode it more often, and at higher combo counts for increased damage

[Sacrificial Steel] and [Sacrificial Pressure] are just good base stats, that don't rely on high combo counters, not that using [Blood Rush] gives you 40% per combo counter (480% max) but this requires a 12x combo counter, which you will not be able to sustain while heavy attacking, [Sacrificial Steel] + [Sacrificial Pressure] on the other hand, gives you a base crit chance of 550% for heavy attacks, and we are only using heavy attacks for this build so, it is very worth it, even without [Sacrificial Pressure], we still get a 440% crit chance, which is better then [Blood Rush] since we don't need a high combo counter fo it

[True Punishment] gives you 100% combo counter chance, which essentially means, every time you hit an enemy, you get 100% more combo (2x more combo) by default i believe you get 4 combo per enemy hit with ta thrown [Xoris], with this mod we get 8 combo per hit, again this lets us have higher combo counters while using the explosive radial attack

[Primed Fever Strike] is very good here, it combines with [Focus Energy] to give corrosive on every attack, note that the [Xoris] already has base electricity, so if your not running [Focus Energy], you can get toxic + corrosive at the same time, which in theory would be better corrosive, but giving up the extra 30% heavy attack efficiency for something else is a tough call to make