QUOTE (Neraph @ Aug 13 2010, 05:48 PM)

Because I'm talking about getting a Power Pact and getting it, not playing a Free Spirit.
So you want to convince your GM that you found the one spirit with 1 Edge and Aura masking? Let's have a look at the rules:
QUOTE ("Spirit pact quality")
The specific nature of the pact should be discussed with the gamemaster and is subject to his approval.
and the Free spirit description:
QUOTE ("Free spirit section")
The gamemaster should consider game balance carefully before introducing any spirit pact into her game or allowing a character to take the Spirit Pact quality.
which is freelancer slang for "this stuff looked really cool when we thought about it at 3am, but by the time we were too drunk to playtest it." So it ends up like all of your ideas: pray that the GM forgot to grow a spine.
That being said, Aura Masking from an Edge 1 spirit is not Extended Masking, more like Slightly Improved Masking. It can only mask 1 extra aura and will never increase later. That will not be enough to mask the typical Power Focus and Improved Reflexes, so getting Masking with your first Initiation will bring almost the same effect for cheaper, and the Masking dice pool will increase over time. You would need a 2 Edge spirit to have a functional Extended Masking, and you can Initiate for cheaper than that. I still don't see why you consider it a must have.
Frankly, if you want to abuse the Spirit pact rules, don't take Aura masking, take Essence Drain and Regeneration

For 5 BP each, of course.