I was looking through SM and couldn't find an entry about what size ally spirits forms can be. I was curious is there had been any 'official' ruling in this regard and what it is.

And on a side note. What would be the base speed on an ally spirit?

Once upon a time there were official rules on the volume range of spirits based on their force, but it was dropped from official material. If you search the forums back 6 months posted by Frank Trollman, you should be able to find the official un-official sizes.

Okies, I will do some digging.

Thanks, Buster

The thread is here but to save time, Frank gave a range of 10-30 litres of volume per point of force, typical human being 70 litres, apparently. I quite like that range if a guideline is going to be necessary.

As to the speed an ally spirit has when materialised, assuming that it's some mundane mode of propulsion like legs, I'd just assign a base rate of whatever was closest. A Force 1 or 2 spirit would probably move at Dwarf speeds. Something Troll sized at Troll speeds and if your ally manifests as a pink unicorn, then it moves at horse or pony speeds, etc.

Personally, I don't see why everyone doesn't have at least one ally spirit in the form of a hawk - it just looks cool.

This thread, appropriately entitled Spirit Volume.

Specifically, Frank had this to say ...