Their House banner is a tree that turns into a sword at the roots. To the Twain this symbolises that nature must be defended at all costs and they are willing to draw arms in order to keep the natural balance espoused by The Society of the Bond.
The Twain live under the king's law but they add to that a much more radical interpretation of the religion of The Bond. This means that most machine's are banned in the Barony of Twain, the lands the House rules over. Their economy is based on agriculture but unlike elsewhere they plough their fields by hand or with the use giant genetically engineered buffalo that also act as their steeds.
Despite the fact that they cannot produce as much as the farms in the neighbouring baronies this devotion to natural methods means that food grown in the barony is highly prized, seen as being healthy and almost religiously redemptive - this means that it fetches a higher price compensating to some extent for the lower production.