Freezing Fog questions

[Just a Guess]

Ancient white dragons have the Freezing Fog ability.

Freezing Fog:

An old white dragon can use this ability three times per day. It is similar to an acid fog spell but deals cold damage instead of acid damage. It also causes a rime of slippery ice to form on any surface the fog touches, creating the effect of a grease spell. The dragon is immune to the grease effect because of its icewalking ability. This ability is the equivalent of a 6th-level spell.

I have several questions regarding this:
1 It states working similar to acid fog + grease. Acid fog states it works like solid fog. So does freezing fog include both the rules for solid fog and grease?
2 Can the dragon take 5ft steps in the freezing fog? He can ignore grease but not solid fog.
3 It states being equivalent to a 6th level spell. Does that mean the grease DC is calculated as a 6th level spell?
4 The dragon can not look through an acid fog, but this is freezing fog, should his snow vision apply?
5 how would it (especially the grease part) interact with the blizzard ability?

[mplindustries]

Just a Guess wrote:

1 It states working similar to acid fog + grease. Acid fog states it works like solid fog. So does freezing fog include both the rules for solid fog and grease?

Yes.

Just a Guess wrote:

2 Can the dragon take 5ft steps in the freezing fog? He can ignore grease but not solid fog.

No, a creature cannot take a 5 foot step in Solid Fog.

Just a Guess wrote:

3 It states being equivalent to a 6th level spell. Does that mean the grease DC is calculated as a 6th level spell?

Yes, the DC would be based on a 6th level spell: 16 + stat.

Just a Guess wrote:

4 The dragon can not look through an acid fog, but this is freezing fog, should his snow vision apply?

Expect table variation, but I would say no. The sight applies through snowy conditions which are a specific thing, not just cloud spells that deal cold damage.

Just a Guess wrote:

5 how would it (especially the grease part) interact with the blizzard ability?

All of the penalties and slow downs would stack on top of each other. What is confusing you about this combination?

[Just a Guess]

Thanks.
I'm going to GM a fight with this, so no table variation, I just want to handle it right.

about 5:
The dragon is immune to the grease effect because it is from ice and his icewalking applies. Deep snow on ice renders the ice rather harmless irl (I know comparing rl and rules is problematic) so I wondered whether both still apply.

Lets sum it up:
Solid fog: 1/2 speed
grease: 1/2 speed
blizzard: 1/4 speed
So you can walk at 1/16 your normal speed. Meaning you'd need to have a speed of 160 or more to move more than 5ft.

The dragon can ignore the grease and the blizzard but not the solid fog and thus moves at 1/2 speed.