Avoid 20 grenades by dodging with your Exo.

Note: This can only be done in single player, and you cannot use your own grenades.

Whenever you see a grenade, you will notice rings around it. If the rings are green, you are out of the blast radius. If the rings are red, you are in it's blast radius. What you want to do for this trophy is air dash out of the circle when you are in the blast radius. This can be done with either exo suit and all you need to do is jump, then press the sprint button ( [ Register or Signin to view external links. ] ) while in the air and move the [ Register or Signin to view external links. ] forward, right, left or down. You will dash in the direction you put the [ Register or Signin to view external links. ] in. So you need to do that to escape from a grenades blast radius. Do this 20 times and the trophy will unlock. You can farm this trophy as well, so if you die or restart checkpoint it will count towards one of the twenty.

If you don't have this by the time you complete the game, load up the fourth mission called "Fission". Once you drop down to the street, they'll be a ton of enemies ahead. Just hang about behind cover and look for grenades. Whenever you see one, run into it and dash out of it. Once the enemies stop throwing grenades, or the enemies get killed by your team, restart at the last checkpoint.