Koei Tecmo is still consistently revealing tantalising new details for Hyrule Warriors in the form of new playable characters, stages and villains. It's the former that arguably raise hype levels the most, as we can all fantasize about crushing hundreds of foes with a variety of iconic characters from the Zelda franchise.
The tweet below, from the official account for the title, has been posted recently to confirm that yet another playable character will be confirmed this week.
The loose Google translation gives few hints, but there are some suggesting that an interpretation of the informal phrase for "goro" at the end points to a Goron; similiar teasing pointed the way to the previous unveiling of Fi. As for which Goron it would be, Darunia seems like a fair and popular option on the grounds that Ocarina of Time is yet to get the Warriors treatment, yet it could just as easily be a character from the more recent home console entries in the franchise.
We don't have long until we find out, in any case. Who would you like to see announced?