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The Voidforge Pike is exclusive to Siptah, which is a DLC, which you pay (goes back to the p2w argument).
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The Voidforge Pike is not accessible (through legitimate play) in the Exiled Lands, except for Single-Player character transfer from Siptah to EL but that doesn’t exactly matter.
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The Voidforge Pike, while having superior damage, has 0% Armor Penetration, which makes a serious difference.
Here are the weapons crafted with a T4 Bladesmith
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Slap a Master Weapon Fitting on both to get +5 DMG and +12% Armor Pen
• Voidforge Pike: 73/86 - 12%
• Bazaar Spears: 62/64 - 29.2%
I’m not gonna say which one is the best, because the value you get out of Armor Penetration varies depending on the target. Regardless, points (1) and (2) keep the argument quite correct, as even if you bought Siptah you will not get the Voidforge Pike in the Exiled Lands.