Welcome, Lego and Portal fans alike! This is a simple design that I came up with while sorting through my Lego collection, and it seemed like a good idea for my first Instructable. Enjoy!

Step 1: Gather the "Ingredients"

There are really not many pieces to gather, so this should be a quick step. You will need: 1 small rifle / pistol. 1 five-way 1x1x1 piece, 1 two way 1x1x1 piece, 2 orange / blue studs, 2 1x2x1/3 plates, 1 1x2x1/3 tooth joint, 1 antenna piece.

Step 2: Create the Center Part

Using all the black pieces and one stud, arrange them as shown. The gun fits into the top nub of the five-way piece. Connect all the other pieces normally.

Step 3: Build the Shell

Connect the tooth joint to the center as shown, then add the other two plates to the sides. After this comes the sad part. Remove the antenna from its base. I know, but we have to carry on. Attach the base to the two-way piece, and discard or store the antenna.

Step 4: Finished

Congratulations, you are now the proud owner of a portal gun! Have fun testing! As was mentioned before, this is my first Instructable. I would greatly appreciate feedback, and I will base future projects off of this projects reception. Thank you!