I accidentally bought the Age of Darkness extension without realizing it was for the updated version of the card game, then idly wondered if it could be made to work anyway as I've played the iPad version of Rivals for Catan and it seems broadly similar to the original card game.
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It would be incredibly difficult to mix the old base game with the new expansions. While similar, the rules and mechanics were completely redone for Rivals. It may be possible, but you'd probably need to reword most of the descriptions for all of the cards in either the base game or the expansions.
By the time you've done all of that, you'd have been much better off just spending the $15-20 to get a copy of Rivals instead.