Urzas ability works well in Humans, as the activated ability uses strictly colorless mana, and while the ability does cost five mana, Aether Vial can be used to help pay that cost, meaning Humans has 23 mana sources to activate the ability if you count fifteen non-Ancient Ziggurat Lands, four Noble Hierarchs, and four Aether Vials
The four main categories are activated abilities, triggered abilities, static abilities, and spell abilities
Nine times out of ten, your commander is the focal point of your deck
It's not a strategy for the faint of heart, and because it requires so much resource investment, it's usually not a good plan to split the difference with another mechanic
It takes four legendary (literally and figuratively) outlaws from Magics past, and gives them the Wanted Poster treatment from Thunder Junction