Of course, some decks may want to run both of them
14 Hour Of Reckoning Hour of Reckoning is almost the inverse of Culling Ritual
Future expansions will likely introduce new printing techniques and design possibilities
However a few do have "practical" uses - here are some examples: The particular card you reference, Garruk the Slayer, was created for the Magic 2015 prerelease and is used in a variant where one player plays normally and the other plays as Garruk
The Pokmon TCG has grown significantly as more players have entered the game, and the game is still more affordable to play than most other card games as the most expensive top-tier deck is currently only about $100
Other than that, it was more or less the same dominance as in Standard: Boros energy and its three color variants immediately shot to the top rank for both usage and winrate, the various build-around energy cards all proved to be at least viable, and even control decks adopted the new energy-based interaction