>>58829896As someone who did a Gen 3 living dex, just go for it. The only problems (if you don't want to use the GameCube games) are the Johto starters and legendary beasts, requiring three playthroughs of Emerald (which includes completing the Hoenn dex) and FRLG (beating the game and triggering the Legendary Beast event, hoping they don't use Roar or else they're gone for good jesus christ) respectively.
I'm still stuck on Gen 2's living dex, mainly because I stopped playing for a bit and don't know where to start again
actually I do, with Yellow and I got sidetracked by mystery gift shit.