Helping Liu Bei fight Lu Bu in "Dynasty Warriors: Origins" is a very troublesome thing in the game, because you can't make mistakes, but many players don't know how to help Liu Bei fight Lu Bu. In fact, brothers who swear to fight against Lu Bu can Quite a while, but even with the buffs, they eventually lose.
How to help Liu Bei defeat Lu Bu in Dynasty Warriors Origin
The three Taoyuan brothers can hold their own against Lu Bu for quite some time, but even with the buffs, they will eventually lose. Theoretically you can defeat Lu Bu with them, but you need perfect execution and almost never make a mistake.
The planned route is that you have to defeat Dong Zhuo with Cao Cao and prevent Lu Bu from breaking through and killing Yuan Shao. Even with Liu Bei retreating, Yuan Shao and his bodyguard were able to hold off Dong Zhuo's forces for a while until they were finally overwhelmed. However, Lu Bu acts as a timer during the battle; eventually, he is bound to eliminate your generals if you don't defeat him first.
If you really want to help Liu Bei, you can follow Lu Bu, but don't jump when he jumps off the cliff. Instead, use the ejection tactic to perform an attack on Lu Bu from above. This should affect his courage. After that, the best thing you can do for Liu Bei is to keep his morale high and defeat Dong Zhuo as quickly as possible.