Derevi Prison (Competitive) (EDH / Commander)

Foreword:
This list was inspired greatly by Glix's list on the Top Commanders FB Page (https://www.facebook.com/TopCommanders/posts/759862224103282:0). I highly recommend reading through this primer first before reading below.

Derevi is a very versatile commander and offers numerous ways to take the deck, which include combo / control (with Deadeye Navigator), token swarm / Time Warp versions, and Prison. I personally enjoy prison as an archetype, and also believe this is one of the strongest strategies in EDH, so that is the focus of this deck.

After some testing with his list, I quickly noticed that I had to mulligan aggressively nearly every game just to find enough mana for the first couple of turns. I've since made some changes that sacrifice some of the explosiveness of Glix's list for more consistency. These changes are also in response to my particular meta, which is 3-4 person pods, top decks including The Mimeoplasm, Edric, Karador, Brago, Prossh, and Roon; these decks are more midrange-y, with combo finishes. No one is playing Hermit Druid or Ad Nauseum Tendrils.

The Deck:
I've organized this list by function for better understanding of how to adapt it to your personal meta. I'll quickly explain each section and the purpose I see that function having.

Locks-
These are the cards will ultimately win you the game. Timing is everything with these cards. Running a Winter Orb effect out ASAP rather than when everyone has tapped out is a mistake. However, Root Maze works better the earlier you play it, optimally turn 1-2. Stasis needs careful setup, etc.

Spheres-
I categorize these cards as anything that increases the cost of a spell. As in, the spell can't even be cast in the first place unless more is paid.

Taxes-
These are similar to the Spheres, but this usually means "you must pay extra or else something unfavorable happens to you." This section is largely made up of cards where that unfavorable thing is getting the spell countered.
Notice that Spelltithe can turn on some combo decks that need to sacrifice permanents.
Kataki is great in metas with lots of mana rocks, but not in ones with a high amount of mana dorks or land ramp.
Rhystic Study is either a one sided sphere against your opponents or free card draw. I love that Study can cause misplays between players.

Hate-
Hate is meant specifically for a type of card or strategy, and is useless if your opponents aren't playing with those cards or strategies. That said, tutoring (Mindcensor), big spells like Wraths (Teeg), activated abilities for Karador combo, mana dorks in general, etc (Linvala), and mana rocks / artifact abilities (Null Rod / Stony Silence) are so ubiquitous in this format that they're rarely dead cards. If any of these types of strategies are completely non-existent in your meta, these can become flex slots.

Board Control-
Willbreaker is nothing short of amazing and steals games quickly. Some other cards could fit into this section, like Aura of Silence since it doubles as removal. Also in this section is board resets (Cyclonic Rift), answers to Humility, and cards that buy enough time to take control of the game.

Draw Engines-
This is an aggressive deck. As such, you often dump your hand and need to refill it. These cards help you not run out of gas and be left dead in the water if your plan A of locking the board down gets interrupted.

Utility-
These cards don't fit into any better category. Prophet is a top tutor target. First, it makes you immune to Winter Orbs. Second, in a 4 player pod, you get 3 untaps before it's your turn again. This offers a great deal of options, such as using Selvala every turn, tutoring with Yisan every turn, locking a player down with Patron Wizard, blocking with Derevi and putting her back into play for 1GWU every turn, or drawing multiple cards per turn with Azami.
Quirion Ranger helps keep a Stasis up and enables more untap shenanigans with Yisan, Selvala, Azami, and Patron Wizard.
Sakashima can also keep a Stasis up by copying Derevi, giving you two untap or tap triggers per creature dealing damage.

Mana Dorks / Rocks / Land-
Currently testing 31 lands ( I don't count Dryad Arbor since it can't be used first turn). I might bring this back down to 30 if I find I can get away with it. If I do, I'd cut Glacial Fortress. I may also potentially cut Adarkar Wastes and replace it with Seachrome Coast.

That's it for now. All feedback is welcomed.