It was made that way back in the days so that Hero Spear (1 handed, which has flame dmg) can be somehow useful using dual wield with 1 handed chaos spear when both their elemental is fire.
Dual wield sux so bad in PK anyway, so it doesn't affect anything, nobody uses them, cuz while you hit let's say 1300 on some1 with hero axe, you will hit like 800 with Hero Spear (1handed) + Chaos spear (1 handed) be it lightning or fire elemental, doesn't rly matter.
Atleast with fire elemental on it it's abit useful vs NPCs / monuments, otherwise it's a crap weapon combo anyway so it doesn't matter. I'd keep it this way to let 1 handed hero spear be abit useful atleast against monuments while combined with 1 handed chaos spear.
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