On top of the pre-constructed decks with cards that cant be obtained otherwise, the included duels can also be played in reverse, and you unlock additional Challenge Duels the same way youd unlock them in regular campaigns, for characters added through the DLCs
Luckily for you, Ive studied and analyzed all eight hundred and sixty one legal white-plus commanders printed at the time of writing so I could present my findings to you as a public service
In Commander, I once built a Sultai-colored tap/untap tribal deck: it was awful, and some of that was intentional, but the point is that with a wide card pool you can find lots of interesting things to do

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