Im using +2 gloves and its always TH3 base
i have tried boosting it to +4 tho and then mob die before i can add on further
however, my pocket proc war is sj thf + dread atma so its default 3, my bounty shot will only add on to make it +4. max i managed to raise is +5 too before mob/nm dies :X there can be "no effect" in between but im sure you can raise it ABOVE EXISTING TH by +2 at least from my personal experience
likewise, idk if another rng can raise it further
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