SoulCalibur 2 was the peak of the series. Before all the weird gameplay decisions, the bad character developments, the death of the franchise with SoulCalibur 6.
SoulCalibur 2 has probably the most iconic guest characters, best stages, best characters of the franchise. The game has plenty of content, and the only thing it's truly missing is Create a Soul.
There are no other fighting games nearly as fun to just open up and mash buttons with friends in. It's simple enough that you can jump in and play without really having to go to training mode to have a good time. There's no long combos, no wall splat combos, just you and your opponent whittling each others health down.
Getting this game on PC with rollback netcode in HD is just what the fighting game community needs right now. With all the disappointments happening in recent memory