Aiming outsized siege weapons poses little difficulty for you.
You take no size penalty for aiming a direct-fire siege weapon larger than yourself. If you operate an indirect-fire siege weapon and miss, you misdirect fire by 1 square per range increment.
Direct-fire weapons impose a –2 attack roll penalty per size category by which the weapon is larger than the creature aiming it. An indirect-fire weapon that misses misdirects fire by 1d4 squares per range increment.
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SECTION 15