Level 37

Total Experience Required 238,579

Level 100 progress: 3.5%

This is roughly the same as:

Killing 398 people in Warzone, or...
Killing 406 people in Execution, or...
Killing 337 people in Wingman, or...
Scoring 85,207 points in Guardian, or...
Scoring 259,325 points in Annex, or...
Scoring 156,960 points in Submission.

Horde (TU4)

Completing 597 waves on Casual, or...
Completing 398 waves on Normal, or...
Completing 299 waves on Hardcore, or...
Completing 239 waves on Insane.

Or a combination of the above. Have fun!