I've never played the first Diablo, but I played Diablo 2 a lot back in the day. I didn't expect I would enjoy it as much as I did. The game is simple and short, but it's close to perfect. Sound and music are worth a special mentioning: the music is mesmerizing and the sound effects are absolutely iconic. You'll find both music and sound in all the other sequels.
I'm no expert in the RTS genre and I didn't mess with multiplayer or the Beyond the Dark Portal expansion. I replayed the two Tides of Darkness single player campaigns in a nostalgia flash, so this review only refers to that. Overall the game still holds up very well - with charming graphics and smooth gameplay. It ran flawlessly on a modern Win11 PC. The only downside is that the campaigns are, without being too easy, a bit bland when it comes to tactics. There's effectively not much to figure out during each mission. I enjoyed the classic RTS gameplay and the dip into Warcraft lore quite a bit and I might try the expansion as well some day. It is supposedly much more challenging.
I played the human campaign back in the mid 90s and decided to play the orc campaign since I read up on Warcraft lore and saw that the orc missions were the canonical outcome. Pros: The game has a lot of atmosphere and charm. I like the VGA pixel graphics. Blizzard was still in its early years and the production quality was far from the quality of later days, nevertheless they put a lot of effort into graphics, animation and small video sequences. Mission and map design is pretty good. It's also nice to see the beginnings of the Warcraft franchise and even though a lot of it was later retconned to fit the expanded perspective of the later games there are many characters and locations that appear here for the first time. Cons: Controls and UI and also general gameplay: Controls are not what you would expect from an RTS. This game is much more Dune 2 than Starcraft or even Warcraft 2. Computer AI is pretty dumb. Winning tactics are finding good defensive formations and luring the computer into them. In the later missions it's mostly about letting your summoned creatures soften up the enemy lines. Path ffinding of your units is abysmal. Conclusion: 3 stars for graphics, charm and Warcraft nostalgia. 0 stars for gameplay.