Troika's Temple of Elemental Evil came out in 2003, adapting an old school tabletop adventure into videogame form while being remarkably true to the then-current third edition of the Dungeons & Dragons rules. It's pretty good! I like the bits where you doss around the village of Hommlet and the piratical cove of Nulb more than the temple of the title, but having a too-large dungeon at the end is just another way The Temple of Elemental Evil is true to the typical experience of a D&D adventure.
SNEG revived The T of EE and brought it to Steam last year, with a few refinements and updates. One much-requested addition was achievements, because modern players demand our motivational trophies I guess. SNEG gave in and added them in a recent update, along with some bug fixes.
Most notably, they fixed a problem with experience gain. While ToEE launched with a level cap of 10, you're supposed to be able to continue earning experience points after that. A quirk of D&D's third edition was that you had to spend XP to craft magic items, and if you wanted to be scribing your own scrolls or whatever you needed a steady income of XP. Cutting that off made high-level crafter-casters a bit pointless, a problem that's now been addressed.
Other fixes make Melf's Acid Arrow deal damage "as intended" and adjust curse removal so that "lifting curses using scrolls or spells should now work more reliably". As for those achievements, any you've already earned should unlock when you load your save, except for ones you get for visiting certain locations.
You'll need to head back to Emridy Meadows and the Moathouse dungeons and all the rest to earn those. Just writing their names gave me a tingle of nostalgia—time for a reinstall, I guess. You can find SNEG's revival of The Temple of Elemental Evil on Steam.
