Void

Void missions are a unique type of mission that do not actually occur within the solar system space. Void missions instead require the Tenno to acquire a Void Key from various sources. Each mission is attuned to the type of key that the Tenno has. An Exterminate Key will generate a Exterminate Mission and a Raid Key will generate a Raid Mission. Each mission type has three ranks, and a key associated with each rank.

Accessing Void Missions
If a Tenno has a Void Key, they simply select the key they wish from their Key Menu next to the play mission button at the top of their screen.
 * You can only select this while you are not grouped or on the planet map.

Once you select the key for the mission type you wish to perform, you can invite other Clanmates or friends to participate in the mission with you. Other Tenno can not join you without invitation. Currently Void Missions use the Orokin Void tilesets.

Rewards
Once you complete the map, you'll be given an extra reward that may be in the form of a Prime blueprint or Forma and your void key will be consumed. The Void Keys are not consumed on Mission Failure.