I figured I'd start this topic since there hasn't been one recently. So, share your first adventures and opinions about the hack if you like to.
As for me, my first hack was either The Tale of Elementia or Kid Adventure. Both are great and have really nice artistic style. But TToE has a really great story and nice 'gimmicks', including with the teleportation blocks. Shame it never got conclusion it deserves.
I can't really remember. It was some time ago. I think 2006 or 2007. Not sure. I found that hack in a German forum back then and I can't remember the name. But when I think about how the overworld wasn't changed at all, I think the Title screen also wasn't changed, so that hack probably didn't have a name to begin with. I remember, that the levels were heavily modified and it had no custom music, custom blocks or custom sprites. The creator of this hack must've been a beginner, since sprites were glitched (meaning they had the wrong glitched texture) and I believe there were one or two stages with no exit or one that was impossible to reach. I still remember how one person was complaining about this in the forum, but another person replied that "A game is still a Game". Funny enough I tried to search for the original forum post about a month ago.
First hack I've ever played is TSRP2, the original one, around 12 or so years ago. I've ever since been taking notes from TSRP2 and applying what I found from my mediocre days of hacking to my own works. Even still to this day, I take notes and (much betterly) apply them to my level design.
I dont entirely remember, though Id think it has to be one of the SMB ports to SMW done by Pac, which were impressive to me at the time. IIRC that was around 2007 or 8. Among other hacks I played afterwards were the Panic in the Mushroom Kingdom games, Luigi's Adventures 1 and 3, MarioX World: Bowser's Strikeback, Super Mario Omega, and the Super Mario Infinity series. Brutal Mario and TSRPR came slightly later for me.
I can't quite remember, but I'm pretty sure it was The New Mario World.
I know the date says it was added in 2013, but it was first released in 2009 2008 and I played it (probably that version?) sometime later.
It was either Super Demo World: The Legend Continues or Super Mario Odyssey (a 2004 demo hack) which was extremely impressive at the time. You wouldn't believe it was made in 2004. Sadly the hack was never completed. Super Demo World hasn't aged all that well but that hack got me interested in smw hacking in the first place so I have that hack to thank for it.