I loved XIII-2, every bit of it especially Caius. Such an amazing villain even if his motives are rather...poorly chosen. The battle system despite being the exact same as XIII's (minus the Feral Link) felt more polished, battles more fast paced despite being roughly the same length, and of course movies had better frame rates iirc. XIII-2 would be my favorite Final Fantasy if XII (12 for PS2) didn't exist).