We integrated mega menu in Chaoz WordPress theme. You can make your mega menu since Chaoz 1.2 version. Follow the following guide to create your mega menu-

• Navigate to Appearance > Menus
• Create your menu and assign it to the Main Menu location

• Click on the Screen Options on the Top Right corner.
• Check the CSS Classes checkbox checked to show the CSS Classes input field.

• Select the top parent menu item that you want to enable the mega menu and add the mega-menu class into the CSS Classes input field and click on the Save Menu button.