You discover that this plane is called Innistrad. Here, you embrace the dark magic of necromancy in an effort to conquer death, which came so close to claiming you. Brimming with new power, you encounter the home of a hermit witch, a perfect opportunity to test your abilities.
The hermit witch has several cards with morbid abilities - abilities that care about whether a creature died this turn - and the witch's creatures outclass Liliana's in general.
Liliana's advantage is that she has hard removal (Bone Splinters and Cruel Revival), and she can reanimate the Hermit Witch's creatures. Since Liliana can easily enable morbid abilities, she can use Rise from the Grave to reanimate a Gravetiller Wurm as an 8/8 (with trample), a Somberwald Spider as a 4/6 (with reach), or a Festerhide Boar as a 5/5 (with trample); if she does so, the witch will have a hard time dealing with that creature (though it's not impossible) and victory should be simple for Liliana.
Once Liliana has reanimated a large creature, it's only possible for the witch to deal with it either by using Giant Growth or blocking with several creatures (or both), but if Liliana holds up a Cruel Revival she can counter those plays easily.