You probably don't think of most mods having live seasons, but for the ambitious Project Diablo 4 release date.
Project Diablo 2's core mission statement is "to maintain the Lord of Destruction experience and provide consistent ladder resets while improving on the game as if development never ceased." The mod features a wealth of item rebalances, new endgame content, useful quality of life improvements, and increased potential build diversity.
Seasons in Project Diablo 2 typically run for about four months, although it's been slightly longer than that since the release of season four, Enlightenment. Some of the big changes and highlights for season five include a new trade site, quick casts, buff timers, improved monster targeting, a DPS meter, shared stashes across your characters, and a new "casual friendly" farming boss called uber ancients that provides an alternative to the usual AoE-focused farming methods.
There's also a huge number of balance changes, alongside some new and reworked skills – if you're interested, all the in-depth details can be found in the official patch notes. There's even a fancy trailer that you can check out below:
Sadly, this mod only works for the original Diablo II, and can't be played on Diablo II: Resurrected. This means you're stuck with the old-school resolution and framerate, although the development team says that the shaders it uses should allow the game to be upscaled all the way to 4K without affecting gameplay.
If Diablo Immortal has given you a craving for loot, and you've already found all those RPG game's next major official iteration.