Back when personal computers were new, several companies released pre-built computers that came with custom hardware and a unique operating system. Others released computer parts and let the user build their own computer with a generic operating system like MS-DOS. One company that built its own PC was Commodore, which also created the relatively advanced Commodore 64 gaming console.

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Commodore called its PC line the Amiga, and, in the 80s, the Amiga had remarkably advanced graphics and sound when compared to the competition. Unfortunately, the Amiga didn't keep up during the 90s, and Commodore went under in 1994. Even so, fans of the system will still pay considerable amounts for old machines and the rare Amiga games that they could run.

6 Abandoned Places 2 ($335)

During the late 80s and early 90s, RPG titles for PCs often featured first-person perspectives that let players see what their characters could see. This would eventually lead to the first-person shooter genre, but before then it was hard to render a first-person world. This led to developers giving such games a big interface that would shrink the first-person area they needed to portray. They also focused their games around dungeons, since they were easier to design and map out than towns and outdoor areas.

Abandoned Places 2 is one such RPG, but the Hungarian developers of ArtGame defied this tradition by creating a game that had as much to do above ground as it did below it. Unfortunately, the developers would get stiffed by their publisher, so they only ever made three games. Together with its rarity, the game's quality has helped Abandoned Places 2 to become a real collector's item.

5 Maniac Mansion ($384)

Back when developer LucasArts was creating its first adventure games (under the company name Lucasfilm Games in the 80s), it developed a separate version of each title for every popular platform. That's why Maniac Mansion, the first game to use the SCUMM engine, came out for systems like DOS, the Apple II, the Atari ST, the Amiga, and even the NES.

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The graphics were detailed for the era, and the game made full use of the Amiga's capabilities. It could also work with a mouse, which was a big improvement over the simple controllers of 80s video game consoles. Between Maniac Mansion's status as a milestone adventure game created by a beloved developer and the Amiga version being one of the best options, it's no wonder that complete copies of it are rare and expensive.

4 Starush ($638)

Today, the French publisher Ubisoft is best known for its sprawling open-world game series like Far Cry and Assassin's Creed. However, back in the 80s and 90s, the company (which styled its name as Ubi Soft at the time) had a very different catalog. One of the studio's more unique titles was 1991's Starush.

Starush is a sidescrolling shoot-em-up that features a lengthy intro cinematic and some remarkably detailed graphics. Players even get to pilot a number of vehicles across all the game's stages and deal with a variety of enemies and hazards. Starush isn't the best shmup of all time or the only Ubisoft title released for the Amiga, but it is an interesting early milestone in the history of what would become one of the biggest game developers in the world.

3 Moonstone: A Hard Days Knight ($1,031)

Mortal Kombat made big waves in 1992 by including gore and brutal deaths in what was an otherwise unremarkable fighting game. However, a year earlier, the game Moonstone: A Hard Days Knight was already pushing boundaries when it came to how much violence a game could depict on the Amiga.

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Moonstone was developed by Rob Anderson and published by Mindscape, one of the bigger publishers of the era. Up to four players competed with each other to get the titular Moonstone, first by moving their character around a board and then by fighting monsters in a beat-em-up arena. Moonstone enjoyed a good reception when it came out, but, thanks to its relatively gory graphics, the game was banned in Germany and never released in the United States. These factors are what make it one of the rarest Amiga games around.

2 The Great Giana Sisters ($1,735)

There's no denying it: The Great Giana Sisters was a blatant attempt to copy the bottled lightning that was Super Mario Bros. and give it to the Commodore 64 and Amiga. Super Mario came out in 1985, and the years following its release were full of new platformers and copycats. Supposedly, Nintendo threatened the developer (Time Warp Productions) and the publisher (Rainbow Arts) with a lawsuit if they continued to sell The Great Giana Sisters, and, in response, the companies quietly pulled copies of the game off of shelves.

However, The Great Giana Sisters was popular among those who played it, particularly because of the soundtrack and the aspects of the game that weren't lifted directly from Super Mario Bros. The game's quality, along with how hard it is to find original copies, are why collectors will pay incredible amounts for this extremely rare Amiga game.

1 Castlevania ($2,999)

By and large, Japanese video game developers have been reluctant to release games on PC platforms until relatively recently. Japanese gamers strongly preferred consoles and arcade machines throughout the 80s and 90s, and so these were the systems that developers focused on. Japanese developers would sometimes try to target the large PC gamer audience in the United States, but they did so by licensing their game titles to third-party developers with more experience programming for PC systems but less experience with making good games.

Castlevania for the Amiga was one such title: its developer was a small Hungarian company called Novotrade, and, while the original Castlevania for the NES was a remarkable accomplishment, the Amiga version is a barely playable mess. Of course, playability is less important to a collector. What's more important is the fact that Konami quickly realized how terrible the Amiga version of Castlevania was and pulled it from shelves soon after its release. Much like The Great Giana Sisters, the Amiga Castlevania is a piece of history that a major developer would prefer that people forget, and for that reason the game commands exceptional prices among collectors who'd rather remember.

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