The Mumbai Add-on for HITMAN 2 has 7 achievements worth 150 gamerscore.
Complete Chasing a Ghost.
Wipe out Kale and Shah with the train, Kale and Rangan with a cement pipe, and Rangan with the fan.
Complete all Mission Stories in Chasing a Ghost.
Complete Chasing a Ghost on Master Difficulty.
Select a Starting Location and use an Agency Pickup to smuggle an item into Mumbai.
Reach Mumbai Mastery Level 20.