They boost the chest's value and round out the Pokmon collecting experience
You wont always be able to do something with that mana, especially in the late game, but it isnt unreasonable to think this will let you play a more powerful card or more cards the turn after you play it, and having that tacked on to a relevant body makes for a nice card I think youll want one of these in most Green decks
The reason for not writing the high stats as original stats is both to constrain them within the long-standing design choice to keep monsters' maximum original stats under 5,000, and also because actually writing these stats, as is the case with the Don Thousand/Monster B and Don Thousand/Monster C cards in the Boss Duel event, would squeeze the number font to comically narrow widths
These Art Sleeves are perfect for Magic the Gathering, Pokemon, Redakai, Dragon Ball Z, World of Warcraft, and more