The Battle of Charybdis IX was a Covenant assault on the planet Charybdis IX in the Charybdis system sometime in 2535, prior to the Battle of the Rubble. The colony world was discovered using secret trackers placed in Covenant weapons the Kig-Yar were selling to human insurrectionists. The battle was brief, with all UNSC forces succumbing to the Covenant onslaught quickly, leaving the planet defenseless to be glassed. The only known ship to escape the battle was the UNSC Midsummer Night, which left to track the origin of the contraband weapons. This led to the Battle of the Rubble.