If you are comfortable with the idea, you could throw a militant Catholic splinter faction at them- a group that wants to recover the artifact for their own nefarious purposes.
The Pope's Swiss Guard could be an interesting antagonist or ally. Rainbow Six did a brilliant write up of the Swiss Guard for T2k some years ago.
https://forum.juhlin.com/showthread....ht=swiss+guard
I include a mostly-Italian marauder group, the
Figli di Iniquità (Sons of Iniquity) Condottieri, and a cult-like Hungarian marauder faction in my Austria Sourcebook, both of whom would probably be interested in getting their hands on the Spear of Destiny.
https://forum.juhlin.com/showthread.php?t=4178
I don't know if your players have reached Italy yet but, if not, it might be fun passing through Austria first.
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