National Destiny: My Multiple Identities Are Perfectly Reasonable

After countless rebirths, he finally gets a system—only for it to abandon him right before the National Destiny trials begin. Left with ten random missions and a mysterious phone, he must navigate a world where powerful allies from different realms answer his call. From tactical commanders to immortal cultivators, from legendary generals to loyal disciples, each identity he assumes brings new strength. But when the fate of the nation rests on his shoulders, will his collection of personas be enough to turn the tide?