For example, if you control Traveling Chocobo ("You may play lands and cast Bird spells from the top of your library.") and Jidoor, Aristocratic Capital is on top of your library, you can play Jidoor, Aristocratic Capital, but you can't cast Overture
None of that makes it scary, though
Loyal Subordinate can drain 9 life from your opponents in combat without having to have you attack first
VENSER, CORPSE PUPPET Were starting off this list with Venser, Corpse Puppet, a legendary creature in Dimir that gives you free value for Proliferating
Unfortunately, energy as a whole isn't super impactful when it comes to the Pauper format
There are many decks in EDH that use the graveyard practically as a second hand, and with the Jace's ability to filter what you toss in there and what you don't is very helpful