He frowns slightly in thought, trying to figure out how to get at the heart of the problem as efficiently and accurately as possible.
—okay, quick illusory history lesson.
An image of the continent forms in midair, set in a circle of ocean that fades out of visibility at the edges. Buildings in the old human architectural style - they look vaguely Bronze Age, lots of stone and clay brick - appear, in stylized simplicity and exaggerated size. Little illusory humans scamper between them, wearing pre-invasion human clothing and going about the business of their pre-invasion human lives. Some of them have a pale glow around their heads, and those ones can do things like construct entire buildings telekinetically, or teleport from one end of the continent to the other, or have silent conversations conducted via eye contact alone without the gestures and mouth movements the other humans seem to require.
After a minute of this, a portal appears in midair over the continent, and elves pour out of it, taller than the humans and with pointier ears. The glow symbolizing magic centers on their hands, and they all have at least a little of it, and they use it to good effect in their immediate conquest of the planet: illusions, conjuration, manipulation of living things. They get the humans subjugated in short order, and immediately exterminate all the ones known to have magic.
Some of the haloed humans manage to keep their heads down, so to speak, and avoid tipping the conquerors off; but then they have little illusory fast-forwarded children, and the children are less discreet, and the elves kill their whole families. A few fast-forwarded generations go by, and a couple of haloed babies appear in families with no prior magic users at all, and when those are found out the elves kill them too, and usually also their parents and siblings and definitely always their children if they managed to hide their powers long enough to have any.
He pauses the illusion and waits for a response.