The creature can be created by a necromancer (using various body parts you may have started finding), and does not need, or have, any associated skills. You will meet a necromancer fairly early in the game, who can make creature, but lacks the means to control them. It will be awhile before you can find that means (easy at level 13, not sure but probably possible around level 10 or 11). Basically you will need access to the full Broken Valley (which you have if you are referring to Lovis' tower), and then explore west of the lake and a bit south.