The AntAgonizer's Costume

The AntAgonizer's Costume and the matching The AntAgonizer's Helmet are worn by the AntAgonizer, who is one of the two superheroes fighting in Canterbury Commons in the Capital Wasteland.

Obtaining
They can be obtained from the AntAgonizer either through negotiation or by killing her. Should you be asked by Uncle Roe to solve the town's "Superhero" problem, the AntAgonizer's costume can be handed over to the Mechanist to end the town's problems. Alternatively, wearing the costume in the Mechanist' presence will turn him hostile. If you hand the costume in to the Mechanist, you can then kill him to get it back.When the costume is given to the Mechanist he will give you the unique laser pistol, Protectron's Gaze.

AntAgonizer's Costume
Wearing the costume out in the world can randomly prompt a child to appear and ask for your autograph. It does not appear to affect how ants interact with the character.

While wearing Mechanist's Costume will open unique dialogue options, it is as-of-yet unknown whether the same holds true for the AntAgonizer's Costume.

The AntAgonizer's Helmet
The helmet can be worn with glasses (i.e. the Lucky Shades) but the appearance is unchanged.

Bugs

 * If you hot key the helmet and equip it via the hot key, it will appear completely black, with no textures or shading, the only way to fix this is to place it into a container and then take it back out later.(Disproved on PS3 version.)