Some attacks have no descriptive text, but most have additional effects that can deal additional damage or affect the battle in some other way
7-cost EustassCaptainKid, 3-cost Roronoa Zoro, 4-cost Trafalgar Law, and 1-cost Nami are the strongest cards in this starter deck, but they can be picked up in other boxes, so you arent forced to buy the ST10 to collect them
The main items are detailed down below, quoted from WotCs official article: Creatures without creature types got some creature types. Some artifact creature cards just said summon artifact and some legendary creature cards said summon legend. For example, the first printing of Rorix Bladewing was a Creature Dragon Legend, but this was changed to Legendary Creature Dragon. Creatures that lacked races got a race. Samite Healer was a cleric but is now a human cleric
It's also a mana-free way to shuffle your library
Sure, its not a hard counter like Dispel or Muddle the Mixture, and it cant counter noncreature permanents like Negate