What does XCOM Enemy Within add?

Related questions

1. Can I run XCOM 2?
2. Do you need XCOM Enemy Unknown to play XCOM Enemy Within?
3. What does Advent stand for XCOM?
4. What is XCOM second wave?
5. Are g2a keys stolen?
6. Is XCOM 2 a good game?
7. What does XCOM stand for?
8. Should I play XCOM Enemy Unknown first?
9. Is XCOM 2 War of the chosen a separate game?
10. Is XCOM 2 harder than Enemy Unknown?

Tags

1. #soldier
2. #unknown
3. #within
4. #announced
5. #abilities
6. #class
7. #upgrades
8. #weapons
9. #expansion
10. #enemy
11. #combat
12. #threats
13. #gamescom