Check out the trailer for episode 10: Clearing Hell – the Battle of Iwo Jima part 3. Notice the extensive use of flamethrowers. Because of the difficult terrain, which often mitigated the effective use of tanks, the Marines relied on flamethrowers. You can see them in action on Iwo Jima in the trailer footage. Below the trailer, a Marine tells the story of what it was like to wield the flamethrower on Iwo Jima.