Notes from author
This was probably done a couple of times already, but I decided, why the hell not? It's a pretty standard quality build to get the max out of your Zwei. Use weapon buffs as you please.
Take your crossbow down any elemental path you'd like. Just not normal. It sucks. It sucks as Lightning Heavy Crossbow +5 too, but hey, Biorr has one, so why not?
If you drop Tower Shield completely, you don't need FaP, so you can opt to use something like Ring of Steel Protection, Cloranthy, whatever you'd like. I've rarely seen Biorr switch his xbow to his shield, so you don't even have to use it.
Havel's is mandatory. It's the equivalent of the Ring of Great Strength that Biorr uses.
And finally, always remember;
Beware the limits of your own power.