Ride a elevator from top to bottom non-stop. Yes, that's possible.

Kill 3 enemies using one Scan-Ball

Drill 100 meters of tunnel using the Tunnel Boring Machines

Complete a level with high enemy presence without dying (must be 50+ enemies)

Kill 20 enemies with your gun without dying

Use the grappling hook as a zip-line

Find a hidden cave using the Terra-Scanner

Fall from 50 meters or more

Kill 100 monsters

Let another team member use your rope to climb

Kill the ceiling tentacle before it kills you on your first encounter

Rappel down the full length of your grappling hook's line

Kill 5 enemies in a row while hanging on the grappling hook

Kill 1000 monsters