What can I use to get more runes?

As a devoted player of the game, I'm always looking for ways to enhance my arsenal. Could you possibly enlighten me on the most effective methods for acquiring additional runes? I've heard whispers of mysterious dungeons and challenging bosses, but I'm not sure where to start. Could you possibly recommend any specific strategies, quests, or locations that might yield a generous supply of runes? Additionally, are there any special items or currencies I should be collecting that could aid in this quest? Your insight would be greatly appreciated.