If a vampiric weapon draws blood, it immediately drains its victim. This considerably worsens the effect of the wound, as a relatively small wound can result in a large amount of blood loss. More importantly, the energy and nutrient content of this blood is transferred to its wielder. If the wielder is wounded, this acts as an immediate transfusion, allowing them to survive their wounds longer and canceling the short-term effects of blood loss. If the wielder is unwounded, this gives them unnatural energy and vigor, allowing them to attack faster and with greater force.
The main drawback of vampiric weapons is that they require a continuous material link between the target and wielder. This means that weapons that separate into parts, such as swordpikes and force flails cannot be given vampiric enchantments. Consequently, vampiric weapons tend to lack reach.
Another drawback to vampiric weapons is that they give no advantage in hitting a target or in penetrating armor. While this is not a disadvantage compared to mundane melee weapons, it must be understood that mundane melee weapons are rarely used, and there are plenty of enchantments to choose from that improve a weapon's characteristics in this regard. Enchanting a weapon in a way that fails to improve its tactical value increases cost without increasing benefit, thus represents a net disadvantage even if the weapon itself is not inferior.
The disadvantages of vampiric weapons can be solved by combining vampiric with other enchantments. For instance, a powered vampiric weapon can use brute force to penetrate armor, then use its vampiric abilities to magnify the injury inflicted and heal its wielder.
Vampiric weapons are most effective in tropical environments, where it is uncomfortable to wear heavy armor. This, combined with the fact that they rely on life magic and are thus a legacy of the Irsidu civilization, makes them particularly popular among the morphed races.