Something like this.
Gary Wise: "I see we both have a Ramosian Sergeant"
Random Dude: "So we do"
GW: "But I`m confused, you see my Ramosian Sergeant here is none other than the Legendary Soo-Yo-Ass, Ramosian Sergeant."
RD: "Is it?" (picks up Unnatural Selection and reads it for the first time)
GW: "She is, but the problem is I`ve just noticed that your Sergeant also bears an uncanny resemblance to Soo-Yo-Ass. In fact there might actually be two of the same Legendary permanent in play."
RD: "Uh-oh"
GW: "Well the only way to solve this would be for the copy of Soo-Yo-Ass that became a Legend last to be buried."
RD: "Poop. Thats some good tech"
In IBC, land of 4-of-Lynx/Knight/Mage the Unnatural Selection is a a nails mirrormatch card.