An exclusive Cortana Avatar Prop is currently being handed out to attendees at Halo Fest.

A card is being handed out at Halo fest containing a code which once redeemed gives you a Cortana Chip Avatar Prop.

This prop appears to be exclusive to Halo Fest attendees and could end up being very rare.

You can check out a video and an image of the prop below.

Source: XboxAvatarGear