I'm reading about Darius I of Persia's campaign against the Scythians, a tribal people who lived on the northern part of the Black Sea. Here's what Herodotus had to say after some encounters between them:

The Scythian kings ... sent a herald to Darius bearing the following gifts: a bird, a mouse, a frog, and five arrows. The Persians asked the herald bearing the gifts was, but he said he had received no orders other than to present the gifts and then to leave at once. He added, however, that the Persians would realize what the gifts meant if they were wise. Having heard this, the Persians considered the matter together. ... Gobryas ... reasoned that the gifts had the following significance: "Persians, unless you turn into birds and fly up into the sky, or mice and descend underground, or frogs and hop into the lakes, you will be shot by these arrows and never return home."^*

Why in god's name would you ever send something like that? I can't fathom a single reason behind it. What do you gain from not having your message properly conveyed? There is no advantage in turning this into some sort of riddle. Do you know why you obfuscate messages? It's because there's some hidden meaning you don't want any interloper to receive, like battle plans, intrigue, or warnings. This is basically a "hey, get the fuck off my land" notice. The Scythians want the Persians to understand it. For example, you're standing on some old man's lawn and he exits his home to give you a lamp and dog fur, which signifies unless you stay on the sidewalk like a street lamp, he will send his dog out after you. I'm pretty sure we'd all think he's nuts. What the hell went on in that Scythian meeting?

"Okay, let's send a dude out to Darius and tell him that he's gonna lose this war."
"Wait, let's give him a bird, mouse, frog, and five arrows instead."
"Why the hell would we do that?"
"I don't know, it's pretty cool. It'd provide a dramatic story later."

^* Herodotus, The Histories, trans. by Andrea L. Purvis, ed. by Robert B. Strassler (New York: Anchor Books, 2009): 333-34.