A Nuzlocke is an informal challenge run of a Pokemon game. The traditional rules dictate that when only the first Pokemon found on a given route may be caught, that Pokemon must be nicknamed, and if it faints in battle it "dies" for the rest of the run. I had never given thought to trying this type of run until a few years ago when Pokemon replays were feelings stale and uninteresting. Nuzlockeing has given me a renewed appreciation for these games - the stakes of battle are higher and the rules give me chances to try new Pokemon a team compositions I would have never thought of. Pokemon like Lanturn have become new favorites!
I will admit, I'm not a perfect Nuzlocker. I usually hack in rare candies to help with grinding, if I encounter the same species of Pokemon I will still catch it, and I made Muncher the ZigZagoon immortal in Pokemon Sword because he is my favorite and I will not allow him to die.
Below is a Hall of Fame for my Nuzlockes! I also included honorable mentions of the fallen soldiers who had great runs. (There were way more dead unfortunately, lol.)

Rest in Peace


Rest in Peace


Rest in Peace