This is a weird deck that I've been making to play competitively. It's made for post-rotation, and I've already been looking at substitutes for certain cards. most cards, however, will stay. It's strong, and is even better post-board. Due to that, it's better to look at it as a 75 deck rather than a 60 deck with extra cards.
First of all, the deck uses Heliod's Pilgrim to do stuff. By that, I mean it can use pilgrim to get control, aggro, or ramp auras, allowing the deck to react to whatever the opponent does and prepare for more.
Next, along with the ramp auras, elvish mystic and kiora's follower combine to help ramp. Follower also has the added bonus of being able to untap a creature, which is why I run it over voyaging satyr.
Next, there's Genesis Hydra, a really powerful card. Since this deck can ramp, hydra can easily become a 14/14, netting you almost any card in the deck. He's hard to get rid of by damage, and if you lay a spectra ward on him, he's near unstoppable.
The last few creatures are the 2 souls and polukranos. polukranos helps against weenie and RDW decks, soul of NPH helps against wrath effects and black destruction spells, and soul of theros can finish a game by making the mystics, pilgrims, and followers huge.
The auras all either control by getting rid of creatures and stopping them from doing stuff, ramp by adding functionality to lands, or power up creatures for a kill. They all have their own uses, and it's hard to go into detail in each one.
Syncopate is used over dissipate because it's easy to get enough mana to play it, and it can be cheaper. I might use dissolve, but that requires playtesting.
Other than lands, the final aspect of the main deck is the planeswalkers. Ajani does everything the deck could want. He gets auras, creatures, or planeswalkers and can power up existing creatures, turning simple 1/1s into 4/4s. The deck gets so much mana from a few lands that Nissa can turn a few into creatures without much worry, and she can untap lands for a beefier hydra (among other things).
The side is based around 5 decks: UWx, green, black, blue, and dredge. While dredge may be Tier 2, it wrecks my deck, so I had some stuff for it.
Tormod's crypt is the anti-dredge card, but it also works well against normal rites decks. I haven't found if it really helps against anything else, but it's still useful.
Fiendslayer paladin comes in against mono black and RDW. It sustains your life so you can go into lategame, and once it gets an aura or ajani counters it can wreck almost anything.
There's another soul in the side for UWx and mono black, mainly for the same reasons I listed for having one in the main.
Extra syncopates are good against almost anything, but I haven't decided the exact scenarios when I'd use them.
garruk and deicide are both good against almost any deck, but again, I haven't decided when to take them over other stuff.
Witchstalker is anti-mono blue, because if you get it from a genesis hydra it's hard for them to deal with.
Survey the wreckage is for mono-green, to get rid of nykthos.
Domestication is useful against almost any deck, but I take it against mono-black so i can steal pack rats or lifebane zombies, and mono-blue where I can steal master of waves.
Last, Hybridization is mainly for mono-green, when they play a big guy, or mono-blue's master of waves.
