Mephisto W is not working

Sometimes Mephisto’s W Skill do make dmg and sometimes not or in my case it’s a ~90 to 10 percent change not doing dmg at all (to creps or hero’s). Maybe I’m missing something but Mephisto dmg output is still strange to me.

Lightning Nova is a Ring AoE, like Jaina’s Ring of Frost.

That means only the outer Ring itself deals damage. Nothing inside the Ring will deal any damage.

You have to hit enemies with the Ring of Lightning Nova itself. Enemies that are inside the Ring take zero damage.