Mummies were an accepted part of everyday life in the city of Naktamun. The last set's embalm ability gave your creatures a second life, as it were. The new ability eternalize is similar. Creatures with eternalize can be reborn as Zombies. But we're not talking about simple mindless servants this time around. These are Bolas's Eternals: a lethal undead fighting force that has transcended their mortal capabilities.
Like embalm, eternalize is an activated ability you can activate if the creature card with eternalize is in your graveyard. To do this, pay the eternalize cost and exile the card with eternalize from your graveyard. You can do this any time you could cast a sorcery, which means during your main phase when nothing else is happening. Just like with embalm, the eternalize ability isn't casting a spell. Things that counter spells won't work against eternalize.
When the ability resolves, you create a token copy of the card. As you'd expect, the process of becoming a champion of a millennia-old, power-obsessed, thoroughly evil Dragon Planeswalker causes some rather pleasant changes. The Eternals are very much undead, so they'll be Zombies in addition to whatever creature types it used to have. They're focused on serving Nicol Bolas and him alone, so they'll be black instead of their former colors. They'll also lose their mana costs, just like creatures with embalm did.
Here's the best part: the token will be 4/4 instead of its printed (and smaller) power and toughness. Many creatures with eternalize have abilities that get better because of their increased power. Even if your opponent manages to deal with your eternalize creature once, it'll be much worse for them the second time around.
Remember those sweet printed tokens that were made to highlight the new Zombie look of embalmed creatures? If you're thinking they should do that for eternalize, I have great news: They did. Each creature with eternalize has a corresponding token.
These tokens are optional play accessories. If you don't have the right token or if you just don't want to use them, you don't have to. But if you prefer your victory to be decorated with the lazotep-coated instruments of your ascendance, you have the opportunity.
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