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
Examples: Imagine every time you could have stopped a Turn 1 Expedition Map with discard and wrecked their Turn 3 Tron and prevented Cedric from ever getting a stamp on his SCG Tour Bingo board
Its something were going to continue to see too, and overall I think its a good thing for the game
You also have to tap a creature to attack with it (unless the creature has some other kind of ability that prevents that from happening)
The creator was even seen wearing the card around his neck when entering the ring during one of his famous boxing matches, making the card seen worldwide
If the Glacial Chasm player has a Crucible of Worlds or a Ramunap Excavator, there is a world where they sac it on their upkeep and play it for turn