Bow accuracy/range/power and so forth can all be altered in 'projectiles.txt'. The other stats (charge, melee, defense, etc) can be altered with 'troopstats.txt'. Both are found in the "Shogun - Total War - Warlord Edition" folder.

Khan7's Center for the Enrichment of STW has a very useful packet of information for beginner modders somewhere under the Downloads section that can tell you a lot more about the basics and specifics of Shogun mod editting.

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My name is Klen Sakurai. I am not a samurai.