Constructing Siege Engines (5e Variant Rule)
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Constructing Siege Engines
Wooden siege engines (e.g. ballista, trebuchet, siege tower, couillard, springald, mantlet) are usually built on-site using materials from the land around the structure to be besieged. This might be timber from felled trees, or pulled from houses.
It a half day to construct 50 hit point’s worth of a wooden siege engine, requiring 2 craftsmen for a Medium object, 4 for Large, 16 for Huge, and 64 for Gargantuan.
Construction can be hurried, halving the construction time. This requires at least half the craftsmen to pass a DC 15 Constitution (Endurance) check. If less than half the craftsmen pass the check, the construction time is not reduced and all the craftsmen gain one level of exhaustion.
Siege engines can be constructed with fewer craftsmen. If the number of creatures involved is less than the requirement but at least half the requirement, construction time is doubled.