Blood Mage Mana Tempest

Major bug with this skill on an Ascended Blood Mage

The spell specify that 30% of mana spent would be added as a mana cost per second.
However due to Sanguimancy, an extra life cost per second is added to the storm.

If this is intended it should at least appear in the tooltip as a "skill's cost" instead of "skill's mana cost".