Boomerang deserves better, it's really unhandy at the moment, that weird angle, awkward upgrades, unable to crit, struggling with shielded enemies, limited range. At least change duration upgrades for rotation speed (more hits, same time), investing into duration makes it return slower (range upgrade does that too*) lowering overall dps on bosses, and you can't really use it effectively against the crowds since it has very little radius and kills fodder in first 3-4 ticks, then just rotating for the rest of duration leaving you unarmed. (Yeah you can switch for main weapon to compensate, but it takes so much effort for so little return it doesn't feel fair).
I tried to build it using elemental proc jokers (fire and shock on slime base, I love that combo on my secondary) it seemed neat on paper since that awkward angle caused boomerang to hit enemy as well as ground below them increasing proc chance significantly, with elemental synergy explosions on top it felt really strong, but in practice it's quite inconsistent. You can't cause stable procs due to boomerang sticking to the enemy on collision and doesn't reach ground so ground hits work more like an option to throw it in front of the enemy, and since it kills weak mobs so easily it won't proc explosions nearly as much as you would like it to (versus crowds when you want it the most), and shields mixed in crowd ruin it pretty badly. You can't throw it in front of the crowd to get the most value from duration because of it, and forced to look for weird angles, using damage on return, throwing in front e.t.c In general it makes weapon way less enjoyable to use. Since there is always major obstacles to use it in theoretically satisfyingly way.


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