In general, I like to avoid tutors, because they have a tendency to make the games too similar. I do usually play one or two in a black deck, but never the actual [scryfall]Demonic Tutor[/scryfall]. However, this is different.
This is all about achievements and there’s actually three levels to this one. Level 1: Four demons with different names. Level 2: Four of the actual Liliana-demons. Level 3: Cast [scryfall]Doomsday[/scryfall] to play the demons in the right order. I don’t know what that is, but that’s why it’s an achievement.
We need those tutors here.
Note that I’ve left out some great tutors, because they don’t fit the theme.
Yes, this means you have to cheat a bit by playing [scryfall]Griselbrand[/scryfall]. But hey, it’s for a good cause. Or alternatively, would Liliana care about your rules?
Of course, we also need our package of Lilianas and Liliana affiliated cards:
Heretical Healer will be the commander, because she’s the only legal one.
The rest? Well, some removal and card draw would be nice here, but in practice there isn’t room for anything other than mana production, so put the other 50 cards there. Around 40 lands and 10 ways to either find them more efficiently or otherwise produce mana.
Next level: Do the same with Nicol Bolas at the helm.