The Terracotta Fragment has a chance to drop from Jonn-Dar, one of the Pandarian Champions. The item summons a warrior who will fight for you for 10 minutes. He seems to have three abilities:
Interestingly enough, he appears to match your level since the rare was only 86 but he was 90 when I summoned him. So I tested him out on a few mobs.
He’s easily one of my favourite drops from the champions, even though you need to equip the item.