Mana + Free Proms + Non-Arcane units

[Micky Onimusha]

This is a bit of a curiousity question regarding spell-casting units who aren't Arcane units and getting free spell-casting promotions.

For example:

I have 2 Death Nodes - I build a Vampire - Will it have the Death II promotion free?

I have 3 Death Nodes - I build a Vampire - Will it have the Death II promotion free?

I ask the same question in regards to Firebows with Fire Mana.

Also, another question, and this one regards Arcane units:

Corlindale begins with Spirit, Mind and Earth I free. If I have 2 Spirit Nodes, will I get Spirit II free, or do I need 3 Spirit Nodes?

Hopefully that's clear I'm just basically trying to see how the free promotions apply when you already begin with one of those promotions free anyway.

 

[Grey Fox]

You always need +1 mana, so for 2 free, you need 3, etc.
And it's only for Arcane units. You can get it when the unit is built and when it upgrades.

 

[Micky Onimusha]

You always need +1 mana, so for 2 free, you need 3, etc.
And it's only for Arcane units. You can get it when the unit is built and when it upgrades.

Just making sure. I knew how it worked for Adepts>Mages>Archmages but was in the dark about anything else.