With hardcore presets carrying no-up-merge, getting into upgraded cards requires entering champ with unupped decks initially. There is some level of control for building collection in hardcore, as if you're going for a specific deck then your current farmer shouldn't use cards from that deck. Here then are some decks considering how to achieve a reasonable winrate vs champ unupped
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Lack of poison hurts
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FFQ has been a recommended rareless champ endurance deck in past, but lack of bypass is painful. Can harvest these cards efficiently from mage. A Give from Mirror could help
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need regrades from appraiser
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