Two mods will easily come up, able to unlock this trophy for you, as you progress through Act I. When you get to the lighthouse, one of the two NPCs near the lightwell, James, will give you a sidequest called Counsel of Despair. Completing this will give you the Torch mod for sticks/bats. Otherwise, a main story quest, Black Hawk Down, will reward you the Shock mod for blades from Sinamoi. Either of these, once added to a weapon, will unlock the trophy. Given the flammability of the zombies hurting you as well, it might be easier and better to just go for the Shock mod since you'd get it from the main story anyway.