Because no one knows how to forge Valyrian steel, the material is extremely treasured among those that have it, and also extremely expensive.

Not only this, but Valyrian steel can also be used to kill white walkers, and it is impossible to break, making them much sought after weapons. It is stronger, lighter, and much sharper than any other material that has been discovered. Valyrian steel blades are far superior than any other sword one can find, even the best castle forged steel. Either way, the secrets to making Valyrian steel was lost in the Doom of Valyria, and has never been found again. No one knows exactly how Valyrian steel is forged, however there is speculation that it was made by the heat of dragonfire, which would not be too much of a surprise considering how much the Valyrians treasured their dragons. The material originated in the Valyrian Freehold, an ancient kingdom that utilized dragons in warfare. Valyrian steel is an ancient material that is no longer able to be forged. The whitewalkers carry Ice Cleaver and Ice Sword The dagger Silence can kill wights but not White Walkers. The dagger Silence is obtained through successfully killing all of the Lannister troops during the opening sequence to the game. Keep in mind that if you execute a lord all lords from across the 7 kingdoms will hate you, and if you send him to the wall all lords in his faction will hate you. It is owned by Paxter Redwyne and can be obtained by either executing him or sending him to the wall. Contrary to popular belief this weapon is not a Valyrian steel blade and as such will not harm white walkers. Redwyne is a custom made sword used by Paxter Redwyne. While not forged of Valyrian steel, these weapons are surely fearsome tools of war in the hands of any wielder.

There are many weapons to be found in the Seven Kingdoms and beyond, often strange and wondrous with an edge to match.

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