120 B.C. Sinope, Capital of the Kingdom of Pontus. (Modern Day Turkey.)
The joy slips from the room as the king starts trembling.
He shakes, groans, and falls out of his chair.
He wretches and throws up.
Attendants quickly carry him to an anteroom, leaving the guests, courtiers, and officers at the luxurious banquet in stunned silence.
Thirty minutes later, Mithradates the Fifth, King of Pontus, is dead.
It was an inside job -- someone on the king's most trusted staff poisoned him. And that left his firstborn, Mithradates the Sixth, in extreme peril.
The throne of Pontus was willed by Mithradates V jointly to his wife, Queen Laodice, and his two sons, Mithradates VI and Mithradates Chrestus.
Unfortunately for Mithradates VI, his mother favored Chrestus -- and was very possible the poisoner of her husband, or at least one of the conspirators.
Now twelve years old and not sure who he could count on at court, the young Mithradates set out on a three-fold plan --
1. Learn of poisons, and build immunity to them.
2. Assess and identify a few people he could trust.
3. Escape from the influence of his mother and brother at court.
Mithradates VI (later, Mithradates the Great) began immediately to study toxicology and medicine. Through his research and experiments, he found that you could condition yourself to an immunity to arsenic (the most common food-additive-poison of the day) by regular slow doses -- and he began doing so.
The young man doubled down on his physical training, and began carrying a dagger with him at all times, including under his pillow when he slept.
He began recruiting and socializing with the sons of court officials who were unpopular or out of favor with his mother, along with a couple other close friends. They started taking hunting trips, and gradually the hunting trips became longer.
A few days after his sixteenth birthday, Mithradates the Sixth and his party left for an extended celebratory hunting trip -- from which they didn't return.
The previous hunting trips, they'd been stocking food, wine, and money in little enclaves outside the capital. Now, they had a full few months before anyone realized they'd taken flight.
Mithradates VI and his party began traveling through all of his father's possessions, greeting the commanders of military fortifications, making inspections, meeting his people.
They had a head-start on any potential assassins, so they took open roads at first. After a few months passed, they kept to quieter ways.
They did brave acts, some light skirmishing and raiding, and big game hunting. Mithradates VI made sure news of his exploits filtered back to the capital, so he couldn't be falsely claimed as dead or otherwise slandered.
Gradually, he won over governors and commanders in parts of the kingdom. He studied the geography of his kingdom, and visited the castle his mother had commissioned as her private retreat -- it was luxurious and poorly defended, financed by loans and bribes from Rome, which sought to make Pontus a client state.
The kingdom did poorly under Queen Laodice's regency; she lived luxuriously, which meant depleting Pontus's resources and giving the Romans ever greater sway over Pontus.
The various commanders and governors in Pontus took a greater liking to the young Mithradates VI, who had the marks and trappings of a soldier and huntsman, not of luxury.
Gradually, Mithradates VI found the stores of treasure and supplies his father had sequestered away in parts of the kingdom. Combining these resources with his charisma and natural appeal to the common people and soldiers, Mithradates VI raised a small military force.
His scouts kept an eye on the capital, and waited for the treacherous queen to go to her luxurious castle. Then, he entered Sinope in force, and sent security forces to arrest Laodice and Mithradates Chrestus.
Later, he'd go on to build a small empire in the Black Sea region, and become one of Rome's most dangerous adversaries. But it all started with a mix of hard work and boldness. Hard work in building immunity from poison, training physically, and recruiting; boldness in striking off from the capital right when he would be most likely to be recognized as a threat to Laodice.