Araenae silk rope is incredibly strong and durable, even more so than normal silk rope. It is also naturally fire resistant, taking half damage from fire.
Common: Araenae silk rope has 10 hit points, hardness 6, and can be broken with a DC 26 Strength check.
Price 100 gp; Weight 4 lbs.
Ironweb: Ironweb silk rope is much more difficult to cut and break compared to common araenae rope, but it's much rarer and more expensive. Ironweb silk rope has 15 hit points, hardness 10, and can be broken with a DC 30 strength check.
Price 500 gp; Weight 4 lbs.