By changing the seed number, you can explore multiple results while keeping the same overall input
So if you want to play the bad guys of LOTR, like the idea of Grixis Control, and want some powerful Graveyard strategies with some Orc / Theft stuff sprinkled in, Hosts of Mordor is the deck for you
This can indirectly kill you against faster decks when you draw it too often
When you cast Flayer of Loyalties, you get to gain control of another Creature, except that Creature becomes a ten-power Trampler with Annihilator and Haste itself
What instead happens is a further drive to find better cards and build better decks for the various tribes
Three copies of Gush seems to be the perfect number, It's a card that you almost always want to draw during a game, but you don't want to draw too many copies either