How to get the Collector Assault Rifle?

The Collector Assault Rifle is unfortunately not directly present in the game.

If you are preordering The Art of the Mass Effect Universe, or if you buy a Mass Effect 3-branded Razer gaming accessory, you will get a code that will unlock you this weapon, but only in the Multiplayer game.

Source: Mass effect Wikia

You can make changes to your save file using ''gibbed me3 save editor'' download here so that the collector rifle is available in single player too:

1. open a save file with editor

2. select the raw tab

3. navigate down to / - 4. Plot /Player variables, and click little square button ... on the right of (Collection). a new window will pop-up.

4. press Add. look to the right at the table with two rows.

5. paste this into the Name field: SFXGameContent.SFXWeapon_AssaultRifle_Collector

6. change the nubmer zero in Value field to: 1

7. press Add to add one more entry

8. paste this into the Name field: SFXGameContent.SFXWeapon_AssaultRifle_Collector.Flags

9. change the nubmer zero in Value field to: 1

10. click OK and the window closes

11. save the changes to a new savegamefile by clicking save at the top icon bar.

Launch game, load the new save and play with collector!