Operating System: window 10
Detailed description: Tempest (whirlwind) does not drain mana if you level up and not let go the button.
What were you doing at the time? Arena fights where I would gain level and still whirlwind to easy victory. lol
How consistently does this happen? every time as long as I don’t let go of the button and I don’t use another skill (even if I keep pressing the button).