This shaman is just packed with value
Thrun, Breaker of Silence Thrun, Breaker of Silence is a very powerful creature
Then, your opponent taps six of there ten mana and plays Mindslaver
If you do, when this creature enters, create a 1/1 token copy of it.) Whenever you attack, choose one Create a 1/1 white Rabbit creature token that's tapped and attacking
Doing some research leads me to see that people also play Obzedat, Ghost Council (amazing with Whip!) and Abhorrent Overlord (very hard to attack through this, especially with multiple triggers in one game.) I like all of them: Ordinarily wed want to play around 25 lands in a deck like this, but given that half of our graveyard-filling spells can net us a land I think its pretty safe to shave our land count down towards the 22 range, especially if we are adding fast mana such as Elvish Mystic and Deathrite Shaman
Ramunap Red isnt interested in playing against a plethora of 1/1 lifelink tokens, and thats exactly what Mavren Fein, Dusk Apostle can deliver, especially if your deck is poor at blocking like Ramunap Red is