I'm a fan of these old school RPG's and I was wondering if there are any other series similar that I could purchase on GoG? I already have the Might and Magic and Ultima series as well, thanks.

It depends on what you're looking for.

Bard's Tale Trilogy is first person grid based dungeon crawling, but with non-tactical combat (like Might and Magic combat-wise, but better in that respect). Dragon Wars is also recommended, though with less of an emphasis on combat/dungeon crawling, and more of an emphasis on non-linear exploration.

SSI made some other games. The Dark Sun games are the closest successors to the Gold Box games, albeit with the entire game being in overhead view. Eye of the Beholder is real-time grid-based dungeon crawling, though I think some of the other games in that genre (like Lands of Lore and Anvil of Dawn, for example) may have better mechanics.

A few Wizardry games are available here. Wizardry 6 and 7 are first-person grid-based games with non-tactical turn-based battles. Wizardry 8 gets rid of the grid, and your party and the enemies can move during battle (though your entire party moves as a unit, so I wouldn't call it tactical). Wizardry: Labyrinth of Lost Souls is like earlier Wizardry games, with the town being just a menu, but I think Elminage Gothic may be the better game if you're looking for this style.

Of course, if you're into D&D based turn based tactical combat, you might try Temple of Elemental Evil or even Knights of the Chalice (the latter even has a demo, though the demo can be rather difficult, harder than the full game).

You might also consider looking into the various Spiderweb Software games, like the Avernum series.

Thanks for your reply. I already have most of those titles but I have put the Dark Sun games on the wishlist and I'm also going to check out Avernum as well, that one looks quite good as well.

I do have the Wizardry games and it would also be great to have the early games (1-5) on GoG as well, here's hoping one day.

If you want tactical combat, the best ones from the DOS era (Nahlakh and Disciples of Steel) are not on GOG, so you may want to try games like the Jagged Alliance games, X-Com games, and Age of Wonders games.
I've heard good thing about Knights of the Chalice as well.
EDIT: And Temple of Elemental Evil.

Thanks PetrusOctavianus, I will check those first two you mentioned, and I also have the X-Com games, I found them a bit hard to play though as there was no tutorial I could see. I already have KOTC and TOEE, and wasn't a fan of the other two.

I did pick up a couple such as Warriors & Wizards, Avernum and Return to Krondor, so I've at least got something to play for now.

Betrayal at Krondor is way better than Return to Krondor.

Yeah, I think Knights of the Chalice comes close.

And of course, if you liked the gameplay of the Gold Box games, there are tons of free adventures available for the engine with Forgotten Realms Unlimited Adventures (FRUA). (Also easier to set up now.)

Unlimited Adventures also comes with a pre-made adventure called Heirs to Skull Crag, which is decent.

Well...it's not indecent.

If you like Avernum, Spiderweb Software also has the Exile series. I think someone posted an open source version, so you shouldn't need dosbox or another emulator. EDIT: Nevermind, I thought the two were separate, turns out Avernum is just a rename.

There was Exile 1-3 (Escape from the Pit, Crystal Souls, Ruined World) from 1995-1997 first of all.

Those were then remade (with sequels) as Avernum 1-6 from 2000-2009.

The company then remade the first three as Avernum: Escape from the Pit, Avernum 2: Crystal Souls, and Avernum 3: Ruined World from 2011-2018.

If you want more cRPGs like the Gold Box games, there are hundreds of modules available for Unlimited Adventures. You can download them through the Gold Box Companion (FRUA_Module_Manager.exe)

There's all the old Exile and Avernum games, you can download more adventures for Blades of Exile and Blades of Avernum. There's also Realmz which copies D&D more closely. You can find it for free online.

If you want newer games there's Low Magic Age which uses the D&D OGL rules and is more of a big sandbox. There's also Crown of the Magister which also uses OGL.

Don't forget Neverwinter Nights 1&2 if you have friends to play with.

I'd also recommend Temple of elemental Evil.

It has really nice turn based combat and was a good implementation of the 3.5E rules at the time.

I was about to ask the very same question. I just recently played through the gold box games and the Dragonlance games. I had only played some of them as a kid, so it was good to play the whole series of each.

Then I moved on to Eye of the Beholder. I remember hating it as a kid, but assumed that I might have a different take on it as an adult. I was wrong. I still hate it.

Thus, I am looking for something else. There look to be some good suggestions on here.