Good Grief! I Transmigrated to the Three Kingdoms and Became a Poisonous Strategist

[Reborn + soul transmigration + System + absurd comedy] (Not invincible, no harem, not brainless.) The male lead unexpectedly transmigrates back to the late Eastern Han Dynasty, where there's no food or drink, resources are scarce, and wars rage everywhere. All he wants is to get back to the real world. What? He has to complete every mission before he can go home? I can't breathe fire or spit water, either?! I'm just a wage slave, why are you picking on me... Fine, then I'll just give up and slack off.