I saw your front page, and btw Romans did use rudimentary Xbows. Actually the first xbow was before the romans, probably the greek Gastraphetes, so don't feel ashamed to use them.
We call our xbowmens manuballistarii, from Manuballistae, one of the first and more clumsy roman models. Luckly, we took better xbow from the barbarians
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