This high powered corner of Magic tends to drive up demand for previously little known cards, the moment they find a place in a popular deck
That body would have a hard time cracking Standard, let alone Modern
The rarity, creature type, and number of evolutions of the cards will be random
Having Buy a Box promos not appear in the main set can be an issue in itself, as the Nexus of Fate coverage debacle showed (Nexus of Fate was only available in foil, and due to curling, was often required to be proxied in players decks at tournaments, which was not ideal for viewers watching coverage)
Features rare and special edition cards, enhancing your deck's strength and uniqueness
In a meta where Tool cards like Giant Cape, Metal Core Barrier, Poison Barb and Rocky Helmet are commonly relied on, this single trainer can disrupt and dismantle carefully constructed setups