DC Comics' Wonder Woman is the best-known and most influential female superhero in the world - but she almost died before she even began her career of crimefighting. While Wonder Woman is one of the most popular female heroes in comics and superhero films today (although it can be argued that Captain Marvel is even more popular now), her early days are not as well-known as those of Batman, Captain America and the like. But in the first issue George Perez's Wonder Woman run, Diana almost dies from the most mundane of injuries that can befall a superhero - a gunshot wound.
George Perez is widely considered to be one of the better writers (if not the best) of Diana's character and the wider world around her. His very detailed and expression-oriented artwork aside, Perez emphasized the more fantastical elements of Diana's world, and stressed the fact that Wonder Woman was from another culture entirely (she even had to learn English when she traveled beyond the island of Themyscira). As a stranger to the outside world, so too was Wonder Woman a stranger to the devastating power the Amazons called the "Flashing Thunder."
Diana yearns for purpose after being brought to life from clay, and thus competes in a tournament - masked - and wins handily. As the Champion, Diana is taken to the Temple of Hades at nightfall, where she is provided magic bracelets and a foreboding warning from Philippus. She carries the Flashing Thunder within a small box, and mentions "...it is a great power which can destroy with but a single clap!" Wonder Woman - who at this point, it must be stressed, still has no idea what the Flashing Thunder does or even what it looks like - agrees. Without hesitation, Philippus readies the Flashing Thunder (a pistol) and quickly fires three rounds straight at Diana.
Wonder Woman is shocked and horrified at the weapon. "By the Gods! What is that thing? Where did it come from?" she questions her Amazon sisters. Wonder Woman's mother doesn't answer, saying that this is no time for tales of horror. She's relieved and somewhat shocked herself that her daughter is still alive after facing the weapon. Unlike Atlanteans or Kryptonians such as Superman, the Amazons are not bulletproof (hence the need for the bracelets) and can fall to gunfire like any ordinary human. As seen in the DCEU Wonder Woman film, the Amazons have trained for thousands of years, but the power of the Flashing Thunder can fell them as easily it as fells soldiers in the trenches of what was then-known as the Great War.
The Amazons clearly do not pull punches while training. The Flashing Thunder is the weapon of the enemy and thus is properly feared; still, it is a shock to modern-day readers to see how close Wonder Woman came to dying before even leaving Themyscira. Wonder Woman would go on to fight many battles, but almost didn't fight a single one thanks to the Flashing Thunder.