The description for the [*DC Comics Deck Building Game: Crisis Expansion 1*](http://www.cryptozoic.com/games/dc-comics-deck-building-game-crisis-expansion-pack-1) says the following:

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> This is not a standalone product. DC Comics Deck-building Game or Heroes Unite is required to play.
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Is it possible to play with *both* at once in Crisis mode, maybe with house rules? Since the deck size in Crisis is the time limit, my first thought is that it could maybe be done if you mixed them all up, then reduced the size, but I'd be interested to know if this works well in practice (bonus points if there is something official that says whether or not they work out together).

To be clear, I know that I can just add the decks together and play without further modifications, but that makes the difficulty far, far easier because you have about 75% more cards (meaning you'll probably never end the game by reaching the end of the deck). I'd like to know if there is a way to play it that keeps the difficulty about the same.