Tie Fighter is indeed the sequel to X-Wing and allowed you to play as an imperial pilot.
Since X-Wing been added to the site recently, you can expect Tie Fighter to follow. Unless, obviously, it is not abadonware. And also the size of the archive might be a problem.
If we don't encouter those 2 problems then you can be sure it will be added someday.
![Shocked](http://www.abandonia.com/vbullet/images/smilies/generic/shocked)
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