Answer: The answer should be these two parts. "...I had to arm wrestle with him for it." and "Then I tied all his arms and legs in knots."
Explanation: These are hyperboles because they are exaggerative. Most likely the person did not arm wrestle with an octopus. Although that would be funny to watch, life is not a Disney movie. Then again if anything he fought the octopus to get away but did not literally tie his arms and legs in knots. The character is exaggerating in order to make himself seem even braver and more courageous than he actually is.
