The only reason Sway isnt even more expensive right now is because its effect is more unfun than it is overpowered. Playing Sway effectively restarts the game (which most players hate), without even guaranteeing that the caster will end up in a better position than the other players at the table
On the other side her colleague, Dai (who requested only his first name be used), does the same his cards protected by red sleeves
Card condition is a key factor, avoiding scratches, bends and color fading is the first step to every card
Still, its well worth tracking down one if you can, as Prosper fits right into Outlaws, generates additional Treasure, and can provide a decently tough deathtouch blocker to discourage opponents attacks
I like Blanka because it is ward Pay 2 life mixed with a heroic Guttersnipe with the Gruul commander size
In an older Standard, Cast Out was a similar removal spell that had Flash