In this video you see a huge beast but i have never seen it.
The huge goatman in town is called Djank Miemes and is only available on the PTR (Public Test Realm) server. He sells caches of gear for bloodshards so that you can easily get full sets of armour / weapons / jewellery / items that have changed in the latest patch.
Thank you for the answer i didn’t do much in diablo although its some time a go since i played it the first time but i still dont know much , for now i’m trying to get GRift 20 i’m stuck at 15 after that i have the gear for my monk i’m trying with a barbarian now because i played a bit more on it