These cards each do something different, and they provide a novelty that some players find intriguing and exciting
Chandra, Torch of Defiance When Chandra, Torch of Defiance was first previewed, I was firmly in the "Red Jace, the Mind Sculptor" camp
(Then planeswalk away from this phenomenon.) The Riptide Phenomenon When you encounter The Riptide, each player chooses one nonland permanent on the battlefield, and puts it on the bottom of its owners library
In the very next set, March of the Machine, Realmbreaker goes smashing into planes throughout the multiverse, setting the stage for an interplanar war
After escaping to Thunder Junction, Yuma found a new life and a new purpose: a hungry and bawling baby cactusfolk, lost and alone
Most of our red-flagging (a way we denote that a card needs to move up in rarity unless the lead makes the conscious choice to keep it) has to do with board complexity