A surefire way to bag this is to add different mods to your weapons, making sure to have at least one caustic weapon, one fire weapon, and one shock weapon in your arsenal. Then, it’s simply a case of cycling through each weapon regularly, repairing and level matching them at workbenches to ensure they stay effective. Breaking green (caustic) and red (fire) barrels will help deal relevant damage to enemies, too, as will bursting blue water barrels near to exposed electrical cables. Like a lot of Dead Island 2’s achievements, this will probably come over time with very little effort.