Completing Challenges | Other A: CM Guide

In total, there are 86 small challenges divided into three categories. At a given moment, only three challenges are active (each from a different category) and you can view them by pausing the game. It's crucial to remember that the remaining challenges, which you haven't yet completed, will remain inactive and you won't be able to check them off even if you've done what their descriptions require. Consequently, focus only on the active ones and try to complete them as you go. It should motivate you that each completed challenge will give you 500 EXP, but they can also raise your statistics or paint your weapons in new patterns.

Note - Challenges can be completed both in the single player campaign as well as in multiplayer. Sadly, you can't ignore the co-op modes because there is a whole category dedicated to playing as a Xeno. In the single player campaign, try to pick your missions in accordance with the challenges' current objectives. For example, if the game forces you to eliminate enemies in hand-to-hand combat, chose a mission where you encounter weakly armed scientists.