The Hawke's Bay Add-on for HITMAN 2 has 8 achievements worth 165 gamerscore.
Complete a Featured Contract.
Eliminate Reynard while Orson showers, from the roof of the panic room, and with a pillow.
Trawl the beach.
Complete all Nightcall Challenges.
Complete Nightcall on Master Difficulty.
Select a Starting Location and use an Agency Pickup to smuggle an item into Hawke's Bay.
Reach Hawke's Bay Mastery Level 5.