Japanese cards are sometimes cheaper due to smaller local demand, bulk print editions, and direct availability in Japan
Sure, trading in one creature for another is not that uncommon these days, but modern templating often only allows you to target opposing creatures
Circle of Power and Queen Brahne create less powerful Wizards, but their other effects more than make up for the difference
Conclusions We built a model of the price of a ficticious Magic: The Gathering playing card, over time, as it undergoes several reprints (in our simple model, each reprint leads to a small drop in price for the subsequent 200 days)
Subsets [edit] Starting with "Lost Villains" and "Puppet Show" in the World Games Saga, Subsets have become an integral part of the card game