Dont worry, if you are gonna make a point of clearing the battlefields, it will take you a little longer... i promise...

Keep a lookout for more keys, from here onwards you SHOULD find abot 6 per act.... (and they normally in weird places, or behind BIG monsters), but yes, everything is still fine.. the other dungeons will unlock as you find more keys.

Happy slashing!!!!!

Your existence alone, is excuse enough for the creation of the entire universe… Il you my darling Jeanne-Dré 