a dozen games in the series being released between 1988 and 1993.
All of the Gold Box games look and play in essentially the same fashion. You roll a party of six characters. Most of the games have overland maps, on which the party is merely a square traveling between cities and dungeons, but the bulk of the game's exploration takes place in dungeons in a first-person perspective. The bulk of a Gold Box game takes place in combat, on a tactical grid. More than most other RPGs of the era, the Gold Box games focus on the details of their tactical combat. A single battle can be quick, or larger battles can take up to an hour. Space and movement are important considerations in combat, unlike Wizardry or Might & Magic. For example, if your character is standing next to an enemy and then moves away, the enemy gets a free opportunity attack.
With all that in mind, it's difficult to differentiate between the various Gold Box games. The original, Pool of Radiance, is primitive, missing several interface improvements from its sequels – most notably a "Fix" command which makes healing between combat much less of an annoyance. The Buck Rogers games are obviously different thanks to their setting. Similarly, I've always found the Krynn games, with their Dragonlance setting, to have more personality than their more generic Forgotten Realms counterparts.
Also, play balance generally improved throughout the Gold Box games' run, meaning the later games are generally better than their prequels (and the latest games have better graphics). However, the AD&D rules also seem to play better through the early and middle portions of characters' careers (levels 5-14 or so), so the middle games in the each series, like Curse of the Azure Bonds and Death Knights of Krynn, are usually the best.
The Savage Frontier series was the latest series released, so it benefits from being the best of both worlds. They not only play smoother, but they also start including some measure of player character interaction. Your characters are not merely combat-focused, but will occasionally say things on their own, making them appear to be part of the story, helping lay the groundwork for Baldur's Gate and other BioWare games. The second game, Treasures of the Savage Frontier, even includes possible romance between one of your characters and a recruitable non-player character – one of the first games to include this now-common aspect of RPGs.
The Gold Box games didn't have the reputation of an Ultima or Wizardry in that era. They were considered too combat-heavy, too similar to one another, and they seemed to show that SSI was too content to rest on its laurels. There is merit to these criticisms: they can certainly be quite repetitive, and eleven similar games in five years is the definition of over-saturating the market. However, they also represented and influenced several of the future paths of the industry as a whole, in addition to PC RPGs more generally.
SSI was far ahead of its time in a business sense. The idea of making games using an official license is now extremely common. The sports game genre is built around licenses, in addition to games based on movies, comics, or even bands. License-based games existed before the Gold Box games, and SSI made other AD&D games using the license like Heroes of the Lance (1988) and Hillsfar (1989). But the Gold Box games demonstrated a level of quality in adapting the license to video games which is now seen as common. SSI's use of a single game engine has also become more and more common. (The Savage Frontier games weren't even developed by SSI.)
The Gold Box series also helped pioneer the subgenre of tactical role-playing games. They still fall under the more general category of RPG than a tactics game, since they lack the long-term strategic considerations of the genre which would become more common with games like X-COM (1993) or Final Fantasy Tactics (1997). However, their focus on space, movement, and tactical choice, with combat as the primary point of the game, make them very close relatives.
Two spinoffs from the main Gold Box series also illustrate just how forward-thinking SSI was: Neverwinter Nights (1991) utilized a form of the Gold Box engine and is arguably the first major online RPG, and Forgotten Realms Unlimited Adventures (1993) – a.k.a. FRUA – gave the player the ability to create their own modules and share them with other fans.
The most forward-looking Gold Box game, however, was probably the original Neverwinter Nights (1991). Arguably the prototype for the modern massively multi-player role-playing game, it gave players the opportunity to play a Gold Box game with other people on the fledgling America Online service. Instead of playing an entire party, you rolled a single character and joined up with other characters. The normal campaign was structured off of the main Gold Box series, and existed primarily to help characters level up. It was popular enough to run until 1997, the year Ultima Online was released, and was only shut down due to rights issues.
SSI's failure to replace the Gold Box franchise helped lead to the collapse of RPGs in 1995. Their successors, like the Dark Sun games, didn't capture the ease and smoothness of play that made the Gold Box games such hits. Unfortunately, SSI's catalog is largely missing from modern direct download sites, so all their classic wargames and role-playing games, particularly the Gold Box games, are difficult to acquire and play today. But their influence over the business and mechanics of role-playing games remains.
Rowan Kaiser is a freelance writer currently living the Bay Area, who also writes for The A.V. Club, and has been published at Salon, Gamasutra, Kotaku, and more. He still occasionally finds Ultima VI Moongate maps and mantra notes when he visits his parents' house. Follow him on Twitter @rowankaiser.