If you've been looking for a way to stop aggro decks from ruining your day, then Rule of Law is the card you need the most.
Arclight decks will have a lot of trouble bringing Phoenix creatures back from the graveyard, and mono-red players will have no power to win sporadically any more. So this looks like a great time to relax and let the games roll in a slow fashion.
But most importantly, it locks out Nexus of Fate decks that can get quickly out of hand if you don't control them. This means that Core Set 2020 has just re-introduced one of the best hate cards in the format.