Pokémon Mystery Dungeon: Explorers of Sky

In terms of mainline games though, I'd probably have to go with Blue version, since it's the one I've spent the most time with over the years

First games I remember playing, at least on console, were Mario Kart 64 and Super Mario 64 on my cousins' Nintendo 64 (which later got passed down to me). I would frequently get Mario stuck in the castle moat and my cousins would have to get him out of it so I could keep playing, haha.