Mirror Mirror has its card name, its card type and its illustrator reversed, which is neat and its effect causes, uh, everything to be mirrored and you swap everything with your opponent
This is also why Wrenn and Six fit naturally into strategies built around multiple planeswalker commanders, where protecting incremental advantage engines matters more than winning quickly
Its cool that it actually changes land types, which matters in some odd cases
Its not that bad if youre running a large inventory, but until you get to this is my full time job status, listing $.25 cards isnt worth your time
Mirrodin 's expansion symbol is a small image of Sword of Kaldra, a card from this set
Echos barely a downside here, since reanimation decks and flicker decks can work around it easily