Overheating (5e Variant Rule)
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A weapon with the Overheating property fires normally for a number of attacks per turn indicated by a following number. After that many attacks have been made by the weapon, there is a cumulative 25% chance that the weapon will overload, rendering the weapon permanently inoperable and dealing 1d8 Fire damage to the wielder. For example, a weapon with Overheating 1 will gain a 25% chance of overloading on the second attack made with it in a turn.