Halo: Campaign Evolved features a standard ending and a secret post-credits scene that not only implies the survival of a key character but also strongly suggests that a sequel is planned. The game's conclusion, achieved by completing the original 10 missions, sees Master Chief and Cortana escaping the detonation of the Pillar of Autumn in a longsword fighter jet.
In the normal ending, Master Chief questions Cortana about any other survivors, to which she replies that they are the only ones left. Cortana expresses satisfaction in their victory over the Flood and the Covenant armada, acknowledging the collateral damage to UNSC marines. Master Chief's line, "No. I think we're just getting started," echoes the original game and points towards a future installment, which was indeed Halo 2, released in 2004.
For players who complete the entire campaign, including the three bonus missions, on legendary difficulty, a secret ending unfolds. This scene depicts Sgt. Johnson relaxing on a beach and watching footage of the original ending on a tablet. Upon witnessing the Pillar of Autumn's explosion, he prepares to board a Pelican. Before leaving, he addresses the camera directly, stating, "See you in the sequel."
This secret scene confirms the return of Sgt. Johnson in a potential Halo 2 remake and directly sets up the events of Halo 2. Additionally, both endings feature 343 Guilty Spark flying through space, indicating its survival and likely journey to meet the Arbiter, which initiates the plot of Halo 2. The implication of a Halo 2: Campaign Evolved is significant, suggesting that a continuation of the original trilogy, potentially including a Halo 3 remake, may also be in development.
While no official announcement has been made regarding Halo 2: Campaign Evolved, the evidence presented in the secret ending makes its development highly probable. Fans eager for more Halo content can revisit the original games through the Halo: Master Chief Collection or anticipate the upcoming remade sequel.