What?!?! Noooo I hope they're not standard again.
Since the previous Battle Arena Deck consisted almost entirely of cards from (older) expansion sets, I strongly believe these EX-cards are from Legendary Treasures. I don't believe any of these cards will be reprinted for the new standard format. That would be stupid. The rotation every year keeps the game fresh and challenges players to rethink their strategies and build new decks. If they would keep reprinting older cards the game would get boring and old.
It's like you people want Darkrai to never leave to format.
Every card has to die someday (except Switch).
And Potion. Maybe Darkrai EX and MewTwo EX will join those cards as never leaving the format.
The only cards that have always been legal for Standard play are the original Basic Energy cards. Both Potion and Switch temporarily rotated out of the game when the very first Modified Format became the Standard Format (under WotC, "Standard" referred to the default format for Organized Play). They were later re-released and thus returned to Standard play but after spending the last 30 minutes trying to pinpoint things, I only know the sets in which they returned: the Legendary Collection for Potion and Expedition for Switch.
Finding correct, precise dates for the rotations as well as major events is proving difficult. The latter is relevant as due to the very different tournament structure, among the semi-competitive players (re: the only ones that cared about a rotating format at the time) most were already using the 2002-2003 format sets (Neo-On or "Neon" Modified) instead of the 2001-2002 rotation (Rocket-On). I can find some information but it is unsupported and sometimes contradict what I recall actually happening (my memory could easily be wrong, but so can Bulbapedia on these matters ). Still, even assuming the rotation occurred after Expedition released (and thus both Potion and Switch were again Modified legal)... it was still a pretty significant gap.
A bit more on topic... I don't mind if Darkrai-EX and Mewtwo-EX remain in Standard via a surprise reprint, but that is because they just aren't the presence they once were and the-powers-that-be have shown few signs of fighting power creep, so I don't expect them to get any better. Basically unless there is an M Mewtwo-EX released that becomes broken by Mega Evolving from the current Mewtwo-EX or some combo with Darkrai-EX, it isn't going to make much of a difference. Now if N is reprinted, it becomes a huge deal; it will remain one of the best draw cards and unfortunately that means we will continue being stuck in a format where you're an idiot for trying to plan ahead or cultivate a good hand... strategies that are normally integral to TCG play. We will retain a card designed to punish competent players and reward those who are not; while sometimes "luck" can result in you being down even the full five Prizes (so that it is 6-1 in your opponent's favor) the solution to that is to minimize variance in the game, not provide a source of yet more luck. ¬_¬
Maybe we'll be lucky and N is a typo if these cards end up counting as an official "new" release with XY-era numbering.
Somebody spoiled the contents.
If true, this sounds pretty awesome! It seems to indicate that Pokemon USA is starting to double down on the Expanded format whic could give some great variety (and give me more use out of these old Full Art Virizion-EXs I have).
Question - what is the source for this news? I'm not finding a press release or anything on the pokemon site... a Google search only leads here and to pokebeach's twitter account, so I'm not going to get excited quite yet.