Nostalrius Begins - Quality wow vanilla realm (1.12)

The 15% mana regen while casting:

Does this count all 6 seconds of post cast in combat regen delay before spirit mana/hp regen kicks in?

Or do I actually have to have my hands glowing/casting a spell?

Your question is pretty obscure to me, but after reading it several times I think I understand you, and the answer is the first option.

Not that I play a Druid / Priest myself, but all spells, tooltips & talents that I know of referring to "while casting" mean "before the five seconds that follow mana usage" during which your spirit regen doesn't apply.

Yes, wording was hard to put onto paper.

But thanks for confirming.