Battle Isle - the game which got two different groups of games into public focus: wargames and German games. Both had had their loyal fan-base before, but both had been small. Tactical wargames turned into a very popular genre following this game. German games stayed a niche market in spite of this game's success.
The game starts to shine with its excellent documentation. You don't just get a few pages crypticly explaining some even more cryptic commands. In the box, you find a manual explaining the game mechanics in a detailed and understandable way, but also an addition reference book listing all available units with all their 'technical specs' and yet another book containing the plot (which circles around evil machines taking over the world - not too original, but way more than similar games have to offer).