I have an emblem from Liliana Defiant Necromancer on the board

1. If a manifest creature which is a face down creature dies, does it come back as the creature?

2. If the manifest creature that dies is a face down land, will it come back?

3. If Liliana, Defiant Necromancer is still on board, but uses her minus ability to go to zero loyalty and get binned, will she come back as Liliana, Heretical Healer?

Thanks in advance.

Liliana, Defiant Necromancer's emblem triggers any time an object that's a creature on the battlefield is put into a graveyard, and will attempt to return that object to the battlefield later on regardless of whether or not it remained a creature after leaving.

If a manifest creature dies, Liliana's emblem will attempt to return it to the battlefield face-up, because objects always enter the battlefield face-up unless something specifies otherwise. If the manifested card was a creature card or a land card, the attempt succeeds and it's put onto the battlefield. (If it was an instant or sorcery card, the attempt fails because instants and sorceries can't be put onto the battlefield.)

If Liliana, Defiant Necromancer herself goes to the graveyard, she will not be returned to the battlefield because she was not a creature at the time she died–she was a planeswalker. She'll return to being a creature card once she's in the graveyard, but that doesn't matter.