Martian Madness

Martian Madness is an upcoming event in the 1.3 update, announced by Cenx in the April Fools' spoiler. It includes several alien-themed enemies, among them the Brain Scrambler, Gigazapper, Gray Grunt, Martian Engineer, Martian Officer, Ray Gunner, Tesla Turret, and an as-yet unnamed tripod enemy. The event also includes an extremely difficult mini boss. The event also adds the Martian Conduit Plating, and two vanity sets, Martian Costume, and Martian Uniform. This event can be triggered after the Golem has been defeated.

The 1.3 music spoiler track plays during this event. (listen)