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Silver vs Non-silver swords

Geralt has two main swords that utilize the Witcher combat styles. One sword is silver and the other is not. Your silver sword is highly effective against supernatural targets, but is weak against mortals. Be sure to use the right weapon for the job. If you're fighting bandits or other human types, use the non-silver blade. Against anything supernatural, use the silver sword. The difference in damage dealt is significant.

Gambling

Playing dice is a semi-quick way to make money. Before playing, save your game. As the dice game proceeds, bet the largest amounts possible. If you win, save your game. If you loose, simply reload your game.