Basically, this is a thread in which to share and record details about catching 'em all. This isn't a dedicated trade thread or anything, but rather somewhere to share your progress and experiences with filling in the 'Dex, as well as asking questions and helping others with things, like sharing tips and tricks.
Topics can include, but aren't limited to, completing Regional Dexes in games past and present, managing to conquer the National Dex, or even managing to net yourself a LiveDex!
So I guess I'll start by sharing a bit of my experience. Never completed any Pokedexes at all, at least in the sense of capturing them all. Always relied on sightings and the like. I just never felt encouraged to gather up all the Pokemon from online trading and local trading, y'know? But in Gen VI, I realised how accessible Pokemon were in that gen, and now, I've got a nearly complete LiveDex, thanks to the GTS and XYORAS's huge Pokemon selections, only missing the Sinnoh & Unova Mythicals (sans Darkrai & Phione) and Volcanion, for obvious reasons. And since they're all upcoming events, my LiveDex will be complete most likely for December. To be honest, I kinda feel stupidly proud of it because I've done what I've always wanted to do with these games, and I'm really excited for Sun & Moon to introduce more Pokemon to collect!
The Kalos Dexes (Pokemon X)
The Hoenn Dex (Pokemon Alpha Sapphire)
The National Dex* (Generation VI)
*excluding certain Pokemon the game doesn't consider necessary due to event status