D:OS 1 had the
Sword of Planets, the probably best unique, just because of the fact, that you could recraft it about every two levels and afterwards buff it for example with Tormented Soul do give it a level depending Str and Dex boost.
Though calling these things 'unique' is pretty missleading, it was probably their best invention regarding together with all those option to improve damage and stats from weapons with crafting. Not sure if this was still possible in EE. In EE you had some craftable weapons, which were improveable if you found the missing pieces, but I think they were hidden so hard, that they were already outdated, when you finally managed to gather all the pieces together. Similar of how Bracchus armor works in D:OS2.
