Back in the day when Bungie opened a new chapter in the Halo universe. Halo 3 ODST tells us the story from a few ODSTs, they are the last hope of the city.
ODST comes with 99 achievments worth 990G, only 1 achievment is not so easy LASO completing the game on legendary with all skulls on is hard.
But if you do it in Co-Op you can do in in about 8h.
At the moment (11.August.2015) the game is worth 3232 TA this is way to much.
Most of the achievments can be done by the first play through. You shoud use youtube.com to get all the Audio logs. If you do that all the achievments should come in about 20h.
+ easy gamerscore, coop fun, more halo on xb1, 60fps
- graphics not that much better, boring achievments, 343i gets money if you buy it,
!PLAY IT IN COOP!
All in all the DLC is worth buying it,