Jace's Phantasm s and Wight of Precinct Six can block powerful creatures, but they can't block 20 creatures: so, I can add 3/4 Silent Arbiter
Again, you can check out your commander's page to look for common card velocity effects
Deck List I've put together an example deck for The Ur-Dragon, and as you might already expect, given the card's popularity, it's ridiculously expensive
Sunspine Lynx Sunspine Lynx makes big statements right up front
As the newest Big Bad addition to Magic: The Gatherings expansive rogues gallery, Valgavoth needs to make a serious impression to stack up next to the likes of Nicol Bolas, Elesh Norn, Ob Nixilis, and more
Aristocrat decks that make and sacrifice numerous creature tokens, for example, are perfect for Mirkwood Bats