Dynasty Warriors: Origins offers three distinct campaigns, each boasting a hidden true ending. This guide details how to unlock the true ending for Liu Bei's Shu faction.
First, complete the Shu campaign. This unlocks replayability of past stages. You'll notice a gold banner next to "The Battle of Changban," signifying an alternate ending. Normally, you help Liu Bei escape while Zhang Fei defends the bridge. However, to unlock the true ending, you must defeat Cao Cao instead of ensuring Liu Bei's escape.

Reduce Difficulty: Set the game to "Historian" mode. The sheer number of enemies makes this crucial, especially if you're not a high-level player.
Strategic Partner: Choose Zhang Fei as your partner. This places you closer to Cao Cao's forces, saving valuable time.
Musou Meter Management: Ensure your Musou Rage meter is full before engaging Cao Cao's main force. You'll face two Grand Tactics: eliminating two officers and defeating 250 soldiers. Twin pikes are recommended for the latter.
Once Cao Cao's army is routed, defeating him should be relatively straightforward. A few more missions follow before the Shu true ending is revealed.
Dynasty Warriors: Origins is available on PS5, PC, and Xbox Series X/S.