I just finished my LeafGreen Nuzlocke (I'll tell you more about it if you send me a private message). It's the 2nd Nuzlocke I've ever done, following my Emerald Nuzlocke. In Emerald, I had 6 casualties total but 3 of them came in the Elite 4 and Champion battles. In LeafGreen, I had 9 casualties total but all 6 Pokemon I used for the Elite 4 and Champion survived. So it had me thinking: are certain games harder to Nuzlocke than others?

For those of you who do Nuzlockes, what do you think would be the easiest to Nuzlocke and the hardest to Nuzlocke from these games: Red, Blue, Yellow, Gold, Silver, Crystal, Ruby, Sapphire, Firered, Leafgreen, Emerald, Diamond, Pearl, Platinum, Heartgold, Soulsilver, Black, White, Black 2, White 2, X, and Y?

Or do you believe it has more to do with the skill of the trainer, the experience the trainer has had doing Nuzlockes, or it's a case by case basis where luck and possibly the starter Pokemon you choose has more to do with it than the games themselves?

This is actually kind of an interesting question, and requires some analysis, and varies depending on the Nuzlocke you follow.

The game that has more routes would be an easier Nuzlocke, because you can get more pokemon.

Kanto games have: Routes 1 - 25, Mt. Moon, Diglett's cave, Rock Tunnel, Viridian Forest, Victory Road, Power Plant, Seafoam, Cinnabar Island, Saffron, Cerulean, Vermillion, Fuschia, Safari Zone, Viridian, Celadon, Lavender Town. And even then, some people don't consider some of those to be "distinct" enough, so you have between 34 and 41 pokemon you can catch in total, not including Sevii.

In all of those, you have some guarantees that are pretty good - Starter, Lapras, Snorlax, Gastly, Jynx and Mr.Mime (if you play with trades), Diglett, Tentacool, Slowpoke (for Leaf Green), Geodude, Bellsprout. I mean, some of these are really good, and should be on your team, especially Lapras.
Edit: How could I forget big blob Snorlax?


Hoenn: Routes 101 - 134, Petalburg, Petalburg Woods, Rustboro, Rusturf Tunnel (early), Dewford, Granite Cave, Slateport City, the Power Plant, Fiery Path, Jagged Pass, the Desert, (Magma Hideout), Meteor Falls, Mt. Pyre, Lilycove, Safari Zone Mossdeep, Shoal Cave, Dive-Hideout, (Sky Pillar), Pacifidlog, Sootopolis, Ever Grande, Victory Road. Again, some don't consider these distinct enough, and you run into trouble. 42 pokemon, up to 59 in Emerald, 57 in R/S.

Some guarantees are pretty good, but most of it is luck. Your starter, Spheal (if you are lucky, or consider Shoal cave as separate), Lotad, Whismur (don't underestimate), Carvanha, Tentacool, Numel / Torkoal, Magnemite is powerful too. Makuhita isn't terrible, and thick-fat is useful. But quite a bit depends on your definition of "distinct," and which starter you choose.
Brawly is a pain, no matter what, but if you start with Swampert, it pays to go straight to Mauville without the Dewford badge, and then come back with other high-level pokemon.

But that's just the start - I'm not going to go through all of the trainers, because that's stupid, but Fire Red gives you more options to raise your pokemon without them being killed by exploding Voltorbs and Electrode. I personally found that the Kanto elite 4, while a higher level, was more of what you could counter, and you were more prepared for it, mainly because you had better guarantees from an early stage. You had Snorlax, for sure, before you hit Koga, Lapras before Sabrina. The only one you were generally not prepared for your rival, and that was a problem.