Henchmen or pets of an ancient white dragon

[MarkVIIIMarc]

A party I DM for will likely start hunting an ancient white dragon soon. Besides Kobolds who would be in service to a white dragon to populate its lair?

This has to be a seriously deadly situation for the level 11-13 group.

I imagine some dead and frozen storm giants will serve as a warning this is a serious task they are undertaking but what else would be around a white dragon? Anything cold immune ithe kobolds could unleash on the party allowing the dragon to swoop in and use its breath weapon while only damaging the party?

[Elistan]

Hands down my favorite would be the remorhaz. Immune to Cold (for your reasons) AND Fire (which the party has prepared). Deals Fire damage, which the party is probably not prepared for. Can swallow party members to remove them from the combat and burrow away. Just all around fun and surprising.

[MarkVIIIMarc]

Those will probably work. The dragon having the party chase him towards where they burrow isn't unrealisticly complicated for a white dragon either, if I recall.

[Temperjoke]

Maybe a group of yeti, or a tribe of humanoids?

[Brookshw]

Well, I recall in a 3e high-powered dragon slayer campaign I accidentally caused a TPK by having the party fight 3 polar bears, while in water, that were guarding a white dragon's lair. Make of that what you will.