I'm not sure it's really relevant to have a Story section on the main page (or really anywhere in the Battle Tactics guide). The expansion really has little (if any) story to speak of. There's no particular order in which the missions have to be played, and the main purpose is to improve the tactics of the player (in fact the manual recommends that players new to TA play the BT missions before the OTA campaign so they can utilize the tactics they learn in BT in the storyline). Despite TA's main appeal (today) being the skirmish and multiplayer aspects of the game, the lack of story in the expansion was one of the main complaints people had at the time of its release.
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