Elsewhere during the conversation with Cate Blanchett, she specifically mentioned that Hela becomes more powerful based on the amount of destruction that she causes. Given the fact that it looks like Thor will have to face off with her at the very end of his journey through space, we can reasonably assume that he will need all of the help that he can get. At least we know he will have Hulk, Valkyrie, and (maybe?) Loki by his side in the battle. Revengers!