Stadium cards introduce ongoing effects that reflect the environment they depict, from allowing additional card draw to affecting the energy cost of specific actions, often affecting both players equally
Its not exactly clear why decks have moved away from old Snappy in formats like Modern or Legacy, but that probably has to do with MTG becoming a more proactive game
A 4/4 creature for 5 is a reasonable rate as well, though as with most of blacks best mana doublers, being a creature is a pretty significant drawback with the amount of spot removal and board wipes flying around
Two players: The game can be played by only two players with less theme, without the attack/protect dynamic, but most of the fun
It had various multiplayer modes such as ranked and unranked duels and a battle draft mode
However, it doesn't protect your bench from "spread" damage like Dragapult ex PRE 73's, Dragapult VMAX RCL 93's, Mimikyu VMAX BRS 69's, Dusclops PRE 36's, and Dusknoir PRE 37's, or Mewtwo VUnion 's