The HITMAN Legacy: Bangkok Add-on for HITMAN 2 has 7 achievements worth 90 gamerscore.
Complete Club 27.
Eliminate both Morgan and Cross in a fall accident and both by dropping a coconut on their heads.
Poach Ivory.
Complete all Mission Stories in Club 27.
Complete Level 5 of an Escalation Contract set in Bangkok.
Select a Starting Location and use an Agency Pickup to smuggle an item into Bangkok.
Reach Bangkok Mastery Level 20.