My insanely broken weapon of choice is doublestrike bow/shuriken with 5 (or 6 on hard difficulty) damage.
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Try cooldown-less 6 damage trap, it is seriously broken and still "easy" to get requiring about 5 update slots, four if you are lucky. Or how about literally any ranged weapon with cooldown-less ice.
I'm not saying that doublestrike shuriken is broken, but I would suggest trying other combos and see which one fits better your fighting style.