Very good series. Just finished playing them all, but still working on Blood Omen 2. Here is a quick breakdown and order you should play;

Blood Omen 1- Birds eye view action/ open world adventure that focuses on Kain's early years. Really good and is what pulled me into the series. Atmosphere is dark and the game is long while offering some challenge. The music/ FMV's are still pretty cool, but obviously outdated.

Soul Reaver- Awesome. Different than Blood Omen in that it's more Tomb Raider/ Zelda esque. Yet it's also similar to Blood Omen 1 in that you get power ups, solve puzzles, and explore dungeons. You play as Razial in a open underworld of Nosgoth. Razial can morph into the spirit realm and psychical realm in-game. Furthers the story of Kain. Again, FMV's, voice acting, music, and overall presentation are top-notch.

Soul Reaver 2- Continues directly from SR1 and pretty much plays the same except Nosgoth is much more linear. The combat doesn't feel as intuitive as the SR1 and there are no boss fights. Since Razial starts off with all the abilities you got in the first game you instead power up your reaver with different elemental forces. Also, puzzles are improved over the original. The graphic engine is way better than SR1 and it looks pretty good even for today. Again, story and presentation remain excellent.

LOK: Defiance- Takes place directly after SR2. You get the best of both worlds! You play as Kain and Razial, each with their unique abilities. Combat is deeper and improved over previous games, but still feels a little unpolished and can get repetitive. Gameplay is more Devil May Cry esque. Visually, it's the best looking, but the game's biggest flaw is the fixed camera angles. They are truly awful and will cause headaches and you will get lost in the environments. Overall, the world is pretty linear. Once again, the presentation is epic as ever and this concludes the series well.

Blood Omen 2- Play this last. Once you play SR2 you will understand that BO2 takes place in a alternate timeline. It's not really directly related to the original Blood Omen or any of the other Legacy of Kain games. It feels more like a side story, but is mostly treated as a standalone title. The gameplay is pretty much a 3d 3rd person Blood Omen 1, but without some of BO1's abilities. It's a bit linear, but pretty cool nonetheless. The atmosphere is dark and gothic like all LOK games, but something about playing as Kain is both evil and badass. You don't really need to play BO1 prior to this it's not really a direct sequel to any of the other LOK games.

Overall, great series you need to play them all! If you must SR-SR2- and defiance are a must. SR1&2 end with cliffhangers so once you start SR1 you might as well play SR2 and Defiance.

The games as a series is amazing. They show the progression far beyond its time. To buy them from GOG don't do it! They basically sold us broken games that they're failing to fix themselves. All the technical issues that come with this are fair to say the least UPSETTING. You can say we wasted money.

There are some issues with the games but not that many. Outside of SR1 which admittedly has (and always had) big technical issues, other games work fine for most people. Now, I realise that you may have some serious problems with running these games, but I'm just pointing out that these are not universal. From what I've seen most problems seem related to Windows 10, and only Defiance's game card states that the game works on that system.

The games are... fantastic. Brilliant writing and some of the best voice acting the industry has ever seen coupled with fun combat and... yeah, okay, I can't exactly compliment the area design or puzzles. They tend to be super annoying.

But, yeah, these are classics for a reason. Every gamer ought to play them.

Revisiting these games for Halloween and the forums here;

Yes, voice acting is probably the best ever heard in any game ever! When games went mainstream a lot of big name actors got roped into doing parts, but the guys who recorded lines for the Kain series are the absolute top of the line hands down. Thankfully the writing is also very intelligent and intriguing, these scripts would translate well to film.

Sadly the puzzle aspect (particularly in Soul Reaver) feels quite dated with the block puzzles and return here with the correct power/rune/key/etc.
Combat is so-so I feel, but gets better in the later games (SR2 and Defiance) with more variety and fun stuff to try.

All together it has ups and downs, but certainly has its place and if you're interested in starting I would try Soul Reaver to get the feel of it since the original Blood Omen isn't available here.