The Spartans of Noble Team participated in an operation to investigate a communications blackout at the Visegrád Relay, a mission which led to the first confrontation with Covenant forces on Reach. During the operation, Kat recovered a data module containing Laszlo Sorvad's "latchkey discovery" from the Relay's console and revealed that the Covenant had successfully deployed their forces on Reach. The discovery led the team to Sword Base, currently under siege by Covenant forces and their corvette. Kat and Noble Six engaged the Covenant forces on foot and repelled them off the site and the airbase.
Intelligence gathered from Noble Six and Jun-A266's reconnaissance mission lead to a large-scale UNSC assault on a Covenant-occupied site. Kat and Noble Six engaged Covenant forces on the groundside while other members of Noble Team provided aerial support. Noble Six assisted Kat in reconnaissance of the Covenant-occupied site, destroying multiple aerial defenses and unveiling a large Covenant installation code-named Spire One.
The destruction of the UNSC Grafton by a CSO-class supercarrier, after the Battle of Viery prompted Carter and Kat to reassess the situation. Recognizing the presence of the Supercarrier as a large threat, Kat suggested to Noble Team to reconfigure a slipspace engine into a makeshift slipspace bomb, which would destroy the supercarrier immediately. Carter, along with Kat, Jorge-052 and SPARTAN-B312, helped UNSC ground forces repel Covenant invaders from a UNSC base, which housed the Sabre Program Launch/Research Range. Noble Team was separated from this point, with Jorge and Noble Six participating in Operation: UPPER CUT while the rest focused on groundside operations.
At some point during the Fall of Reach, Kat and the remaining members of Noble Team assisted the UNSC in repelling the Covenant from civilian population centres. They reunited with Noble Six in New Alexandria and helped in the neutralization of Covenant communication jammers and the evacuation of ONI personnel. Soon, Noble Team was hailed by its supervisor, Colonel Urban Holland, and was ordered to destroy 'Sword Base'. The team was forced to enter a radiation bunker to shield them from the Covenant's glassing of New Alexandria. As Noble Team exited the elevator and ran towards the bunker, the Sangheili Field Marshal in a Phantom overhead shot her in the head with a needle rifle, killing her instantly.