Graveyard decks in particular create an engrossing standoff, since it can be terrifying to risk accidentally accelerating your opponents plan but if you have at least some tech to target the yard, you can also force them to keep their own sequencing a lot tighter than they might be used to
Undergrowth is a blanket term for abilities that care about the number of creatures in your graveyard, like the one found on Golgari Raiders
Alesha, Who Smiles at Death, and Mana Confluence
Create a token that's a copy of one of its halves, then unlock it
Both of these were important for me because it made the cards feel more real, rather than using previously used planeswalker card art, which, in my opinion, makes it feel less exciting
Basil Hypnotized Mouse has found Owl prints with droplets of water, hinting that part of the Hexwell Crown has been found and taken by this Owl