You sacrifice the Redcap, but it'll come back with a -1/-1 counter thanks to the persist mechanic
1 Swiftfoot Boots
Back in the old days of Magic (like ten years ago), single card prices were based mostly on their age, availability, and playability
In many cases, buying the challenger deck, and the upgrades will save you a few bucks, but the cards youre replacing dont just disappear, they still add value to your collection
Brave the Elements can finish the game by letting us crash through blockers with little to no regard for their presence, while Eerie Interlude not only retriggers all our enters-the-battlefield effects (which gets silly with multiple Thalias Lieutenant) but also lets us dodge Wrath of God, Supreme Verdict, and any other non-damage-based sweeper
Its a fun design and its not every day you get to design your own card and put your face on it