Players can attack with multiple creatures at once
When the opportunity cost is that low (the real cost is playing that many basics in the first place), theres a cap on how powerful the rewards can be and how compelling the interaction points are in games that involve it
While many of them would be interesting spaces to explore and delve into from a design perspective, they're still only filled with untapped potential (at least, at the time of writing)
Walking Ballista Walking Ballista is obscene
It has all of the cards available in the current rotation, and, based on the three hours I had with the game, absolutely appeared to stay true to core MtG
Generating a mana advantage easily escalates into dominating a game with the right deck, and its generally used unfairly to Reanimate something nasty on turn 1 or empower a storm deck