I created a Gnome Barbarian who carried around a small sized Greataxe, and a few alchemists fire in a Spelljamming campaign. While "grounded" to the ship, and pulling a small town through the phlo (don't ask), I noticed that the area below the ship was filled with demonic creatures that were beginning to pile on top of each other in an ever increasing pile of bodies attempting to reach the ship, which was only about 50' above them. Anyone who's familiar with the Phlo knows exactly how volatile it is towards fire... So, not seeing any other option than letting them continue to pile up until they could reach me, I casually flung an alchemist's fire down into the pit, and watched as a large portion of the town was enveloped in a fireball and destroyed. This was at level 3.
Same game my friend's character jumped onto a ballista and fired it at the demonic creatures. Rolled a 20. DM said to roll for confirmation. Rolled another 20. DM requested he roll again. Rolled another 20. Was told to keep rolling until he didn't. He rolled a total of four 20s in a row before he rolled something else. The DM said he fired through the first three, killing them outright, and to roll damage for the fourth, which was also enough to kill him. It was a good game...