Sierra On-Line is a classic example of the rise and fall of a gaming company. The 1980s and 90s were the golden years for adventure games, and few companies took advantage of this period more than Sierra. The company started as a modest tech startup in the Los Angeles suburbs, and during its height, was one of the two biggest names in the adventure gaming community.

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Sadly, as storytelling became more common in other genres, adventure games dropped in popularity and Sierra went down with them. The company had become a shell of its former self by the early 2000s, and, at this point, "Sierra" is hardly more than a brand name used by other developers. Still, fans of the company remember its games fondly, and collectors will pay a pretty penny for complete boxes from the studio's early catalog.

All prices were taken from PriceCharting.com and were accurate at the time of publication.

6 Space Quest 3: The Pirates of Pestulon ($140)

space quest 3
Space Quest 3.

Loose

$63.70

Complete in Box

$140.67

New

$607.50

One thing that Sierra loved to do for its adventure games was to put the word "Quest" in almost every title. The Space Quest series focused on Roger Wilco, a spaceship janitor who goes on a series of increasingly outrageous adventures.

Space Quest was one of the company's most successful series, partly because of the sense of humor and satire of the lead designers, Mark Crowe and Scott Murphy, and partly because of the way each story builds directly on each other to create a single memorable journey. Space Quest 3: The Pirates of Pestulon picks up immediately where Space Quest 2 leaves off, and features improved graphics, sound effects, and a more intuitive text parser compared to the first two games. It won awards when it came out in 1989, and it's still a popular collector's item today.

5 Space Quest 2: Vohaul's Revenge ($146)

space quest 2
Space Quest 2.

Loose

$59.68

Complete in Box

$146.75

New

$313.97

Space Quest 2 came out in 1987, two years before Space Quest 3. It didn't break as much ground or improve as many features as the third game did, but it did solidify the satirical tone of the Space Quest series and introduce new mechanics, puzzles, and parodies.

In Space Quest 2, Roger Wilco ends up as a janitor again despite his heroics, and he's also the target of Sludge Vohaul, who was secretly responsible for the crisis of the first game. Original copies of the game came with a short comic book that explains what happens between the first and second games, making the complete box especially valuable to collectors.

4 Freddy Pharkas: Frontier Pharmacist (Sierra Originals) ($175)

freddy pharkas
Freddy Pharkas: Frontier Pharmacist.

Loose

$78.20

Complete in Box

$175.96

New

$351.92

In 1993, Al Lowe, who normally focused on the Leisure Suit Larry series, decided to create a Wild West spoof along the lines of the film Blazing Saddles. He and co-designer Josh Mandel wound up creating Freddy Pharkas: Frontier Pharmacist.

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Much like Leisure Suit Larry, Freddy Pharkas has an unusually adult sense of humor, though it may have helped that the game came out a year before the ESRB rating system came into existence. Unlike Larry, Freddy would never get a sequel, but it was popular enough to get a CD-ROM version a year later complete with voice acting for every character. The later CD-ROM editions are particularly rare and valuable.

3 Quest for Glory 4: Shadows of Darkness ($405)

quest for glory 4
Quest for Glory 4.

Loose

$69.89

Complete in Box

$405.51

New

$811.00

Sierra's Quest for Glory series was an adventure-RPG hybrid, an unusual sight back in the late 80s and early 90s. The main character is a player-named adventurer who solves puzzles, fights monsters, and improves his skills through constant practice instead of getting levels or skill points. The whole series was co-designed by married couple Lori Ann and Corey Cole.

Fans often regard Quest for Glory 4 as the best game of the series. It features what may be the strongest set of characters and storylines, is the first game in the series to feature voice acting (including narration by actor John Rhys-Davies, who played Gimli in the Lord of the Rings trilogy), and has a dynamic and action-oriented combat system. It also didn't go through the development struggles of the last game of the series, Dragon Fire.

2 Space Quest 1: The Sarien Encounter ($520)

space quest 1
Space Quest 1.

Loose

$235.71

Complete in Box

$520.03

New

$1,040.00

Space Quest 1 came out in 1986, at which time most graphical adventure games were more like text adventures with some simple illustrations on top. The King's Quest series started before Space Quest, but this title was the first Sierra game to feature the sense of humor that would become a staple of the company's later releases.

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Space Quest 1 would quickly become a new hit for Sierra, but it was something of a gamble back when it first came out. Combine that fact with the game's importance as a landmark for the company, and it's no wonder that Space Quest 1 is one of the rarest Sierra games out there.

1 Gabriel Knight: Sins of the Fathers ($679)

gabriel knight sins of the fathers
Gabriel Knight: Sins of the Fathers

Loose

$305.65

Complete in Box

$679.99

New

$699.99

Sierra covered a variety of story genres with their various Quest series, from fantasy and science fiction to police procedural. However, it wasn't until 1993 that designer Jane Jensen convinced Sierra to let her create a supernatural murder mystery called Gabriel Knight: Sins of the Fathers. The story takes place in a detailed rendition of New Orleans, and it features an amazing music score and a star-studded vocal cast that includes Tim Curry, Mark Hamill, and Michael Dorn.

Gabriel Knight would only get two sequels, but only because Sierra's fortunes were already in decline during the late 1990s. Like other Sierra games of the time, Gabriel Knight came out both as a set of floppy disks without voice acting and a multimedia CD-ROM edition with voice acting. The CD-ROM edition is prized by collectors because of the higher quality of the game, the comic-book prequel that came in the box, and the box itself, which had a unique triangular shape for the initial release.

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