The Exodus set introduced different-colored symbols, and MTG rarity symbols were used on all cards going forward
A mill deck uses a strategy that depends on emptying its opponents library, rather than reducing their life total
A new card type, especially with a rules-bearing subtype, is an exceptionally high amount of work, but this is a pretty great example of how additional tasks fall out beyond the obvious work necessary to implement new mechanics
Yawgmoth is a mono-black creature who can set up powerful or even infinite combos with his abilities, centered on sacrifice and -1/-1 counters
Heres a look at each new Commander Deck, courtesy of Wizards of the Coast
You may cast any number of spells from among those nonland cards without paying their mana costs