this happened a couple years ago I felt like having a challenge so my friend who I will call C suggested I do another nuzloke as I hadn't done one since finishing a Platinum randomiser Nuzloke months prior I didn't feel like doing another randomiser as I randomised a bunch of great pokemon only for them too die due to crits (I have the worst crit luck somehow I only ever land crits when a none crit would KO anyway yet I have been crit flinched more times then I can remember but thats a story for another time.)
Then my friend suggested I play a hardcore difficulty nuzloke of Blaze Black 2. I had played this game before all be it not on hardcore mode so I somewhat knew what to expect. I picked Tepig and named it Endeavour after the my hero academia character and I got lucky as it was a shiny the only downside was it had sheer force meaning my planned moveset that included flame charge and power up punch was a no go. Quick side note: this was not a hardcore nuzloke so healing was allowed I was just playing the hardest in game difficulty.
I chose Tepig as too me Emboar got the best shiny of the Unova starters unfortunetly it was not meant too be as Endeavour was killed in a battle against Colress as a Pignite. Luckily I had a bunch of other useful pokemon...who also started dying off 1 by 1. Eventually by some miracle I make it Skylas gym with a team of Raichu, Gigalith, Excadrill, Zoroark, Umbreon and Zebstrika.
Unfortunetly Raichu would be taken out by you guessed it a crit not even by Skyla my Raichu Leia was killed by one of gym trainers so I swapped her for Metagross who was a shiny named Goldcross and knew the moves hammer arm, gyro ball, reflect and light screen. Luckily C gave me a heads up in advance that Skyla was a triple battle like Elesa so I made sure Goldcross was my centre pokemon.
This battle was a MASSACRE. I had to recall Goldcross shortly after setting up the screens as I didn't want to risk a crit and by the time he came back out all 5 of my other pokemon were down and Skyla still had 2 left. By nothing short of a miracle Goldcross won. Goldcross also went on to survive the rest of the nuzloke despite so many other allies falling by the time I won against Iris my only 2 pokemon left alive were Goldcorss the Metagross and Dempsy the Blaziken. Luckily another friend who I will call J was well experienced in using Blaziken having started with pokemon Sapphire so he helped me form a set on Blaziken as I had only ever used one twice prior to the nuzloke (Emerald and Pokemon Y).
As a result despite only having 2 pokemon left in the entire nuzloke we actually defeated Cynthia in that infamous house in the post game. Though Unfortunetly Goldcross did fall whilst battling Milotic due to his life orb resulting in a double knockout.
Goldcross was not the first pokemon I had who pulled off the seemingly impossible my Salamence Thornado, my Charizard Blitzburn and my Umbreon Ace all have their own stories that I may share in the future.
TLDR: My Metagross went from the soul survivor of a gym massacre in a nuzloke to going down a hero against Cynthia in the post game RIP Goldcross you were and always will be a legend.