If you've ever played a strategy game based off of world history like Civ, Age of Empires, or Rise of Nations, you've probably heard of Cyrus of Persia. He upended lots of the old power structures in the Middle East, taking out the Medes, Lydians, and Babylonians before finally falling in battle to either the Massagetae or Derbices, a tribal people on the Iranian steppes. The ancient writer Herodotus details Cyrus' campaign against the Babylonians:

When Cyrus was advancing to Babylon, he came to the River Gyndes.... Now to cross the River Gyndes requires boats, and when one of Cyrus' sacred white horses audaciously stepped into the river and tried to cross it, the river's current swept him underwater and carried him off. Cyrus was extremely angry at the river for its insolence and threatened that he would weaken it so much that in the future, women would be able to cross it easily without even getting their knees wet. Having made this threat, he postponed his expedition against Babylon and divided his army into two units, one for each side of the river. Then, surveying with a rope, he marked out the ground for 180 channels on each side of the Gynes and leading from it in every direction. Because his labor force was large, this work was finally accomplished, but not until they had spent the whole summer there working on it. Thus Cyrus punished the River Gyndes by dividing it into 360 channels. ^*

Imagine for a moment you're enlisted into the army, thinking you're going to enter glorious combat against one of the most powerful cities in history, and then your commander tells you you have to stop for the summer and dig because the king is pissed a river had the gall to drown one of his horses. Imagine you're in Babylon, hearing a powerful force is coming, and then news arrives that Cyrus needs to deal with an uppity river first. Man, this guy clearly has too much disposable income. Do you know how much money it takes to have an army? You have to feed them, the animals, and the baggage train. All this for one horse! It'd better been Pegasus or some shit.

^* Herodotus, The Histories, trans. by Andrea L. Purvis, ed. by Robert B. Strassler (New York: Anchor Books, 2009): 102.