Once Awake

The player is then tasked to a Grineer Spy Mission on M Prime, Mercury to collect three data units for retrieval from a Grineer Asteroid base. During the mission, the Grineer Dr. Tengus is revealed through intercepted transmissions to be working on "specimens" to be used in the development of his bio weapon.

After the first data unit is recovered, Tengus' assistant express anger that the Tenno are there, demanding absolute secrecy in their project and thus ordering the marines to assault the Tenno.

After the second data unit is recovered, panic breaks loose as the Infested has broken free from quarantine, with the effect of Infested units now appearing to fight both Grineer and Tenno. Despite of which, it appears that there may be an unknown third party involved, as the Grineer soldiers blames Dr. Tengus for the outbreak, while the Lotus implies that someone else released the Infested on purpose.

After the third and final data unit is recovered, the Lotus briefly explain what the Infested are and how they disappeared a long time ago.

A later mission takes place in Terminus, Mercury, where players are tasked with exterminating all Infested units aboard a Grineer Galleon overrun by the Infestation. after completion the the lotus sends a copy of Dr Tengus' reports to the operator: "The additional test Marines have arrived. The specimens tore through previous batch much faster than expected. It should be noted that Marines who survived the longest were using fire based weapons."

Plotting to destroy the infested, The Lotus sends the Tenno to Lares, Mercury, in an attempt to destroy the Infested there by using a Cascade Bomb planted on the asteroid's power core, that will use Void energy to eliminate all organic life while leaving the structure intact.

The Cascade explosion worked and the asteroid has been purged of infestation. But the threat cannot be so easily contained. Doctor Tengus' experiments with his plague are grossly irresponsible and have threatened the entire system. "All that is needed is an infected ship to reach a populated area and we'll be unable to contain its spread. There's no controlling it, the Grineer will be in just as much peril as we are." warned the lotus. Around this time a message is intercepted from Dr. Tengus said to be for the queens. Believing that the tenno plans to use spores of the infested against him, he begins development on a countermeasure for the plague.