Mission 3 Cliffhanger
After planting the C4, head toward the next objective and nearby you should find an enemy isolated from the rest. Come behind this enemy and knife them in the back without being noticed.
Here is a video guide with English commentary!
Here is a playlist of guides for this game!https://www.youtube.com/playlist?list=PL-HeW6XkKdUK97oYVSMU7...