I also completely forgot to mention Rifts somehow, when it’s a pretty big change.
Basically, now there are two gamemodes: Original, and Rifts. Rifts is only available whenever a season is running. Right now, a season is not running.
Rifts is a temporary gamemode where nothing you obtain is kept between seasons or between gamemodes (other than you keep vault/char slots, and pet skins, in the Rifts gamemode), but the drop tables, drop rates, and Fame gain have been adjusted likewise. You don’t get to bring a pet over, but each season you start anew and can hatch and level a pet to maximum Uncommon or Common, depending on the length of the season (and perhaps depending on future seasons, who knows?)
Each season offers changes to the Realm. For the last 2 seasons, they’ve been going for a veteran/WS-style Realm. It’s not quite the same, but plays off of it. The next season will be a different idea entirely, apparently, and we don’t know what it will be yet.
It’s not everyone’s cup of tea, but I personally find it really fun, even if I’m nowhere near the top 50 on the leaderboards. I just enjoy playing the game and building up a character casually. Since drop tables and drop rates have been changed (in the last 2 seasons, dungeons dropped greater pots instead of regular pots, and UT drop rates, including those of event whites, were higher), I don’t really feel like I’m “wasting luck” or anything. Plus there’s something to be said about how the game plays when everyone has an uncommon pet at best