Blink and You'll Miss It

Ephemerate card art

Magic has many cards with "enter the battlefield" abilities. Like Coiling Oracle below:

The effects can be powerful when they trigger only once. What if you could make it happen again? That is the very concept behind a 'blink' deck.

In Magic parlance, blinking a permanent is when you have it leave, and then immediately return to, the battlefield. There are many cards that do this, most often in blue or white. Cards like Ephemerate or Ghostly Flicker:

Now, I should be more precise with my terminology: it's not leaving and returning to the battlefield. Blinking means a permanent is exiled and then it enters the battlefield (ETB) again. So its ETB ability triggers again. That's powerful. It also counts as a new object- and this is an important nuance.

Since blinking a creature makes it count as a new object, it is a way to evade removal spells. If, for example, an opponent plays a Murder ("destroy target creature") targeting your Coiling Oracle, you can respond by playing Ephemerate, also targeting your creature. Ephemerate is the top card on the stack, so it is first to resolve. Coiling Oracle is exiled and returns to the battlefield (triggering its ETB ability- handy). And it is a new object, so when your opponent's Murder resolves, there is no target, and the spell was wasted. Powerful! But not necessarily intuitive.

Most of Magic's rules make sense to me. But I always struggled with this one. Why doesn't the blinked creature count as the same creature? The answer is in the comprehensive rules, rule 400.7:

400.7. An object that moves from one zone to another becomes a new object with no memory of, or relation to, its previous existence.

That's all there is to it. Blinking means moving from the battlefield to exile (another zone) and back to the battlefield. That means- among other things- that any counters on an object go away if you blink it. So there are drawbacks as well as advantages. Either way, it is an important rule to remember.