Giving your opponents counters works out well in EDH because you can make a friend, and you can even broker a deal to give somebody an Oblivion Stone or something should that seem like the best option
Its potential damage output (up to 130 with Blaine) makes it a formidable choice for beginners
Of these, Izzet Phoenix is the clear standout - though this powerful archetype got nerfed pretty hard when Expressive Iteration got placed on the banlist
Why yes, Id love to double up on Breach the Multiverse, Demonic Tutor, or Expropriate
Then you put Mind Rot into your graveyard
You get to attack relentlessly because your creatures won't take damage, and in my experience, when your whole team is menacing, several get through unblocked