You can soft-lock players with cards like Meren of Clan Nel Toth, Abiding Grace, and Tortured Existence to prevent anybody else from having a meaningful combat step
Granted, just because an eBay auction closed at a certain price point doesn't mean that the sale itself has been completed, as there's no way of knowing whether the winning bid was actually paid
For example, Greninja BREAK is infamous for being able to put damage counters on your opponents Pokmon, getting around most defenses, and setting up a possible knockout
From the cards we've seen, it looks like Tarkir Dragonstorm does a great job of balancing the two while also keeping things new
From what I know, there are over 160 different English/Japanese cards for Latios and Latias combined
While the number of listings for Ponies: The Galloping on Mercari fluctuates, you can sometimes find a good deal