If you mean Pure Rune of Kalastor I have something on the far back burner that I haven’t tested yet but Rune of Kalastor even outside a specialized build is pretty damn good
In the build GT, that 1p Kalastor + maxed Ignition has flat fire damage per projectile on par with Hagarrad, which means a dedicated Kalastor setup will likely have more paper dps than hagarrad. The problem is that it’s a lot more inconsistent in shotgunning due to the way the projectiles work. I’ve tried a pure Kalastor build in 0.4 and it’s significantly slower than this build when against bosses but it’s still pretty damn good.