rage of the valkyries - improving spells?

[HHeplo]

Originally Posted by thufir11

Viking Vortex is still level one - how to improve this spell? There is written in manual that when gaining new level you can enhance your rage spells but it seems to be not true..

..and why doesn't the manual simply tell you, that you can't gain any levels on it until you find the 1st valkyrie, if it's a game desing ?. = Feels still more like bug.

Is this annoying "desing" only there, 'cause there's some kind of an achievement about not using rage in combat ?.