(Blank stare.)
Original intent...
Evidence: exhibit invisible...
Cibryll's "Legend of the Death Knights" fiction takes place in an alternate timeline where Serenity wore the Dark Armour...
Ilina dies, gets revived on the planet Deathorak as undead... helps out with defeating the titular death knights...
During AS's development... I decided to create the canon (to me) timeline replacement of undead-Ilina as someone else... Xenoa Valimyuka (Pic 3, pink-haired girl right of Shane), killed in the LSC before January 2015, I think...
Now glad Cibryll made those pics and a text file with their names... :-b
So did Ilina ever fight Serenity in that timeline? In the canon timeline(?) she's alive (and there must be a timeline where she dies and stays dead).
In regards to the Solar Shadow games, SS1 has Serenity die and be resurrected as Shadow Serenity though this isn't canon to either the series itself or to the XSP. Solar Shadow 2 has Serenity alive though she ends up brainwashed before being freed.