Level 9 was a British developer of computer software, active between 1981 and 1991. Founded by Mike, Nicholas and Pete Austin, the company produced software for the BBC Micro, Nascom, ZX Spectrum, Commodore 64, Oric, Atari, Lynx 48k, RML 380Z, Amstrad CPC, MSX, Amiga, Apple II, Memotech MTX, and Enterprise platforms and is best known for its successful text adventure games until a general decline in the text adventure market forced their closure in June 1991. Level 9's first release was an extension to Nascom BASIC called Extension Basic. The first game, also for the Nascom, was called Fantasy and was similar to Valhalla, but with no graphics. Other products from that era were Missile Defence, Bomber and Space Invasion — all for the Nascom. The tapes were duplicated and sent out by mail order by the brothers based on orders generated by the classified advertisements they ran in the Computing Today magazine. They were originally based in High Wycombe, Bucks before moving to the West Country. A-code Level 9 devised their own interpretation language, A-code, around 1979. It was very memory efficient, mainly due to the advanced text compression routines which could compress texts to about 50%. The game data, which was identical for all platforms, was incorporated into the executable file for specific machines, together with the interpreter part. A-code underwent a few revisions: there are three distinct versions in all, plus several extensions which form new A-code versions of their own. (Level 9 A-code should not be confused with the A-code language developed by Dave Platt in 1979 for the purpose of writing the highly popular 550 points extension of the original Adventure game.) In some ways A-code and the A-machine virtual machine were even more impressive than rival Infocom's ZIL and Z-machine; both companies initially designed games for computers with 32K RAM and ZIL was in many ways more sophisticated. But Infocom products of the era required a disk drive, alleviating the memory restrictions of the platforms of the time. Level 9 due to different dynamics in the British market had to deliver their text adventures on cassette tapes, which generally meant that programs had to be loaded in one go and that they had to completely fit into memory. Andrew Deeley, who worked for Level 9 on Software Development, recalls how the use of the A-Code interpreter enabled L9 to produce hundreds of cross platform