Darksteel uncommon. When a set contains a strong “X matters” theme - that is, when a certain mechanic, zone, card type, or style of play is featured prominently - most on-theme cards reward their controller for staying on theme. Another common way of playing out the theme, though, is with cards that punish the opponent for not following it. Chimeric Egg pushes the Mirrodin block’s artifact-heavy nature by giving you a 6/6 trampler for every three times your opponent breaks theme.
