If you can find a way of untapping Thriss repeatedly, such as Seedborn Muse, you can make use of his ability multiple times per turn cycle, making combat with you a prospect your opponents wont want to face
Between cards like Skullclamp and sacrifice outlets, its easy to get the full value off this little zombie
Cheating out creatures with great ETB effects or something like Etali, Primal Storm with a powerful attack trigger is well worth the 3 mana
Planeswalkers don't stick around in Commander that often, especially ones that need to survive three or more turns to use their ultimate
I like a lot of stuff that deals exactly 1 damage but at the rate they release new commanders, no one can really agree on a deck because by the time you get cards, they have announced 3 new sets
Hapatra, Vizier of Poisons and Slimefoot the Stowaway play the attrition game well, but go about it in very different ways