Collective Brutality: This has been played in Abzan since it was released because it does everything the deck wants to do. Discard possible answer cards, kill small creatures, win Goyf fights, get some life back vs. burn, and make extra lands useful.
Inquisition of Kozilek: Classic turn 1 discard. This deck has
Darkslick Shores
to help cast it turn 1 painlessly, and it will almost never be dead that early.
note: Why no
Thoughtsieze
? A few reasons. 1) More discard would most likely take the place of counterspells, since they do similar things (keep cards from hitting the board), but discard becomes dead mid game and counterspells can stop answers off the top. 2) This deck shocks itself a lot with the mana base, and bob hurts you as well, so taking 5 on turn 1 from fetch+shock+TS is not what I want to do. 3) Aside from planeswalkers, Eldrazi, Titanshift stuff, and tron spells, almost everything I would grab with TS you can get with IoK for no damage.
Mana Leak: One of the reasons to go blue: counterspells. Mana leak and Remand are generally considered to be some of the best counterspells in modern, but I went with leak for a few reasons. First, with the way modern land bases are set up it might as well be a hard counter. Second, if I'm countering a spell I never want to see it again. Third, this deck only runs 6 counterspells, so it can't use remand for shenanigans in a counterspell fight the way control decks can.
Spell Snare: There are just too many good 2 drops in modern that pierce can't counter and that you never want to hit the board, Snappy and Young Pyromancer being the main offenders.
Vendilion Clique: Thoughtsieze on a 3/1 flying stick. Sure, your opponent gets another card, but it makes up for that by beating 1 lingering souls in a race, being a flying body, and having the flexibility to sift through something in your hand. The fact that it can be cast draw step isn't bad either.