X-Cutioner's Song, perhaps?
Be an obvious way to get Stryfe, plus DIRE redos of characters like '90s Gambit, '90s Rogue, and '90s Jubilee. The originals, of which, are OUTRAGEOUSLY expensive (or not even able to be located in Jubilee's case) on the aftermarket nowadays.
Also, yeah, yeah, Stryfe is technically Cable, but IDC. He's basically Cable's Reverse-Flash as his identical foil, and is just one of the most important villains in the X-Men mythos period for being responsible for the outbreak of the Legacy Virus at the end of XCS.