As Gavin Verhey explains, there are four Commander decks in all, and each deck comes with at least two different creatures that can command that deck, and for this set, you have your choice of a hero (each of the four heroes are in an adventuring party) OR a fearsome monster
You don't have to change much to make them viable in an average deck, and they present interesting puzzles involving a certain amount of risk
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It poops out little dudes to protect itself, it resurrects all your weak creatures (who may have fallen while protecting it), and if you're already in a fairly comfortable position when you cast her, Elspeth closes out the game in no time, turning anything you pick into a highly relevant flying threat
You don't necessarily have anything to do in the short term if you keep these two, but if you draw a land in your next two turns you can cast it