The following achievements are available with the bonus downloadable Flashback and Combustible Map Packs:

Achievement	How to unlock
Annex: Now With Execution Rules ( 75 points )	Win an Annex match on each Flashback and Combustible Map Pack map (public matches only).
Bound by a Shared Past ( 15 points )	Win a Wingman match on each of the 5 Flashback Map Pack maps.
Forged in the Fire ( 15 points )	Win a Wingman match on each of the 3 Combustible Map Pack maps.
More Mystery, Less History ( 15 points )	Win a multiplayer match on each of the 5 Flashback Map Pack maps (any mode except Wingman).
Skeletons in your Closet ( 20 points )	Complete waves 1 through 10 on all Flashback Map Pack maps in Horde (any difficulty).
The Roof! The Roof! The Roof... ( 15 points )	Win a multiplayer match on each of the 3 Combustible Map Pack maps (any mode except Wingman).
Trial by, and on, Fire ( 20 points )	Survive first 10 Horde waves on Combustible Map Pack maps as a team.