This format gives you the option of playing with a pool of cards thats larger than the current Standard, but not as large as Modern
There are plenty of instances in which that will be enough, but theres more
8 Crypt Rats Common Board Wipe Crypt Rats is one of the very few board wipes that are available at the common rarity, making it widely played in Pauper decks that want something like that in their deck (primarily Golgari Gardens)
Fascinating and versatile cards appeared in sets like Duskmourn: House of Horror (DSK), Outlaws of Thunder Junction (OTJ), and Murders at Karlov Manor (MKM)
Emrakul, however, can take the combo players turn and use it to make them self-destruct
It gives you a consistent and diverse creature base to copy on top of options on how to interact with your opponents