[Tenet Plinx] built for primary fire, although the bomb is still usable. If you don't have a riven swap it for [Primed Heated Charge] or [Primed Fulmination]. If you swap for [Fulmination] I also recommend [Synth Charge] to lean further into the alt fire. I use Secondary Deadhead over Secondary Merciless because with high accuracy and no recoil but only 10 rounds, the 3x headshot multiplier is far more sustainable than the 12x kill multiplier.