Just started watching this ep online, but so far I don't care for they way the writers have Arthur behaving. He has been getting kinder, more understanding, and more determined to handle things differently than his father. Then all of a sudden at the start of this ep he's back to being an ass who gleefully kills a unicorn. I wish the writers had done it a little differently, he still could have been the one that killed it to allow for the rest of the story to occur, but it could have been an accident of some kind instead of completely regressing his character.
Oh well, I'll finish watching and hopefully the rest of the ep will be well done.