A foil rare or mythic of anything special, and this we can indeed calculate: Given that rares are twice as common as mythics, your odds of any specific rare from these four categories is 1/63, and for a particular mythic its going to be 1/126
WERE IN THIS FOR THE LOOT In general, we simply want to maximize ways to put at least one creature card into our graveyard on each players turn
Affinity, on the other hand, is generally the aggressor
Her triggered ability makes a legendary Dog token, but luckily, you get to choose a name for each token - that way, you get to control multiple legendary Dog tokens since they'll all have different names (and will let her attack trigger work better)
With Courser, Fetchlands and Shocklands hurt significantly less and the top card of your deck is almost guaranteed to be gas
Fun : This is where most commanders fall