Basically, we show players a book with all the cards from the set and ask them to pick out their favorites based on different criteria (mechanics, art, flavor text, etc.) One of the questions we asked for the Invasion godbook study was what are the best cards in the set based on mechanics (or game play)
Its the same type of removal as Imprisoned in the Moon or Bound in Gold: An Aura that you attach to a permanent to make it unusable
Between the main set and the pre-constructed Commander decks, Tales of Middle-earth adds four Sauron cards, and Sauron, the Dark Lord is easily the most striking
But the 4 damage mode is likely to pull a lot of weight in this deck too, since Eshki is capable of pressuring life totals so effectively
Grabbing a card from your graveyard may seem redundant, but it can create some powerful loops, especially when copied
Oathsworn Vampire and Feast of the Fallen are probably the two best examples of this, and they both rely on Innistrads worldbuilding to be successful