Again, blink is a highly supported theme and lots of creatures need to do something when they enter the battlefield because your next turn isnt guaranteed in Commander
Today, most counterfeit cards are designed to pass various tests like the bend test and the light test, and some look almost exactly like the real thing, even upon close inspection (unless you're going really deep and using a jeweler's loupe, which is a good way to weed out fakes but too much work for the average player)
When a creature thats blinked is removed from the game it returns either on the abilitys resolution or at the beginning of the next end step
Put one of them onto the battlefield tapped and the other into your hand, then shuffle
In Standard that's pretty great, you get three cards for the price of one
While, in specific contexts, they are the best cards the game has ever seen, our answer to this question actually lies outside of these cards