In the upcoming Diabloid December, players will be able to customize their abilities using runes. In the new video, the developers showed what can be done with such skills as Frost Strike and Thunderous Typhoon.
Runes allow you to endow abilities with additional effects, such as an increase in the radius of application, an increase in damage to enemies under the effects of control, a chance to freeze, and others. They can also be combined to create completely new effects.
If you missed the previous December Ability videos, you can watch them at the following links: first, second.