Geralt, like most other witchers, carries two swords in The Witcher 3, but there is a practical explanation for this design choice. Some may not know how much The Witcher 3 game differs from the show, and there is very little explanation behind the two-sword design in both. As monster hunters, witchers require specialized equipment to bring down the various magical and mundane creatures that plague the land. The swords are an extension of that with both blades being of a different material, one made from silver and one made from steel.
The reason for the steel and silver blades is that each is suited better for the killing of particular targets. In the games, the steel blade is entirely dedicated to taking down a witcher's mundane, non-magic foes such as the various human enemies they are likely to encounter. The silver blade, a sword from The Witcher 3 but omitted from Netflix's show, is especially suited to taking down monsters as silver has anti-magical properties that are effective against most monsters whose origins are of a magical nature. In the Witcher 3, this is translated in-game by having enemies resist damage taken from using the incorrect sword type. For this reason, most witchers carry two blades, but exceptions do exist.
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While witchers like Geralt have always carried two blades, their reasoning has shifted over time and between mediums. Silver was not always the antithesis of all monsters, and the introduction of a steel blade is a recent change. As Geralt frequently must do to survive his ordeals, all witchers adapt to their circumstances and change over time.
Traditionally, in the books, witchers carried two blades, one meteorite and one silver. This was
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