As you walk into your LGS, you spot your local commander group preparing for a game. You glance at their commanders: Oloro, Lord Windgrace, Atraxa,and Meren. "How banal" you chuckle to yourself. These plebeians are completely lacking in originality. The decks are little more than goodstuff, except for the Windgrace player, who appears to be playing the precon. You force yourself into their pod, unrolling your GP Massachusetts 2006 playmat. "Prepare to see an elegant, stylish deck." You say to them as they take turns reading your commander.
Diaochan is a deck for people who want their deck their deck to force people to ask the 5 "W"'s in commander.
Who is that commander?
What does she do?
When was she printed?
Why would you play that over Daretti/Feldon/Grenzo/Another mono red commander?
How does her ability work again?
You don't play Diaochan because she's a strong monored commander. That honor falls to Godo, or _maybe _Krenko. You play Diaochan because she's an elegant, stylish commander, that few others play. Being originally printed in Portal 3 Kingdoms, and only reprinted once in Commander's Arsenal, it's a fair assumption that even seasoned EDH players may not know she exists. By sitting down to a table with Diaochan, you're sending a message. "I know more about this game than you.
Diaochan's ability, at first, looks incredibly clunky. Kill two creatures, but my opponent chooses one? And it's portal speed? But upon closer expection, Diaochan's ability is indeed the greatest power move in the game. Your opponent doesn't get to kill a creature of their choice, you let them kill a creature of their choice. This is where the most readily apparent aspect of any Diaochan deck comes into play: The protection. By giving your creatures shroud, pro-red, or invincibility, you protect them from Diaochan's own ability, and in doing so send a message. "You can only kill what I want you to kill." In practice, Diaochan's ability makes them kill a creature you don't control. Or maybe they kill a creature you want to die. If the only legal targets are your Solemn Simulacrum, your Hoarding Dragon, and an opponent's Steel Hellkite, what do you think they'll pick? In this situation, every option helps you. Or maybe they just target one of your creatures with invincibility, and waste a perfectly good removal spell you so generously gave them.
The problem with Diaochan is that you're playing mono red. Sometimes, your opponents will have things you can't deal with, like enchantments. Fortunately, Diaochan's ability helps with this too! Politics is the name of the game in EDH. Who's the most threatening person at the table right now? Who are they threatening the most? You want to encourage rivalries with Diaochan's ability. If a particular creature is giving a specific opponent a hard time, maybe let them choose what to kill. If they kill it, the creature's controller will see that it was them who killed their creature, not you. Diaochan can't put much presence on the board early, so keeping your opponents angry at each other is one of your best tools.
Typically, you want your opening hand to have at least two of the following: Card draw, ramp, and protection. Diaochan herself is slow to get down, so every mana rock or land acceleration helps. Given that you generally want to protect Diaochan the turn she enters, you may not be able to cast her safely until you have 6-9 mana. This is easier than it sounds with cards like Myriad Landscape, Terrain Generator, and our rocks.
Second, you want protection itself. Diaochan doesn't need much to start impacting the board. She and some greaves are really all you need to start exerting control on the game. After that, you'll still want extra protection for other creatures you'll play later, whether they're utility like Magus of the Moon or just big boys like Wurmcoil Engine. Many of our creatures don't necessarily mind dying to Diaochan, but for the most part you still want to avoid it.
Finally, card draw helps you find both of these things, and more. Card draw is always good. Do I need to elaborate more? Because we're mono-red, we unfortunately don't have much straight card draw, but at least we get rummaging and looting effects, unlike those chumps in monowhite. We also get exile effects such as Outpost Siege, which are great. Early game they can occasionally exile something we would have liked to see, like a Wurmcoil Engine we can't cast, but it's well worth it for the sheer value they provide through the mid and late game.
Card Choices
Card Draw/Advantage-
Cathartic Reunion, Faithless Looting- The good red rummage and looting spells, respectively.
Smuggler's Copter- It's been a while since looter scooter has terrorized standard, but it does plenty of work in this deck. In addition to being card draw, it dodges most wipes and Diaochan's ability.
Chandra, Flamecaller- Reusable wheel+1 on a stick. If you don't need to wheel, the other two abilities aren't shabby either, either helping clear the board, or if the board is already clear, whittling down your opponents.
Combustible Gearhulk- Kinda? Most people will simply take the damage, but honestly it's not a big deal. We have enough graveyard interaction for that not to upset us too much. Gearhulk itself is also a prime Feldon target.
Endless Atlas, Mind's Eye- These are the bones WotC have thrown mono-red and mono-white EDH players, and they're pretty great cards for that. Mind's Eye demands removal, or you fill your hand up at at least 3 cards a turn rotation. Endless atlas is slightly less impressive, but in mono red, it's still some of the best we'll get.
Outpost Siege, Commune with Lava- Prime examples of red's new favorite form of card advantage. Outpost siege can be compared to drawing an extra card every turn, while commune demands more mana, but gives you more options.
Skullclamp- It's skullclamp. Turns Kher Keep and Trading Post into card draw, and acts as pseudo-protection by making your opponents wonder if it's worth killing your Inferno Titan with Diaochan if you just get two cards off it.
Ramp-
Burnished Hart, Thaumatic Compass
, Solemn Simulacrum- These get more lands onto the field or in our hand, which is great. Burnished Hart in particular is a favorite of mine, and goes in almost every non-green deck I build. Thaumatic Compass flips into a second copy of Maze of Ith when you're done ramping, and Sad robot is pure value, and doesn't really need to worry about Diaochan's ability.
Caged Sun- Doubles your red mana. What's not good about that? Lategame lets you produce more mana than you know what to do with.
Everflowing Chalice, Mind Stone, Hedron Archive, Sol Ring, Thran Dynamo- Your typical colorless rocks. If this list looks a little light, that's because it's surprisingly easy to find land ramp in this deck. Mind Stone and Hedron Archive also double as card draw, something we can never have too much of.
Removal-
Blasphemous Act, Comet Storm, Magmaquake, Molten Disaster- The best mono-red has to offer in terms of boardwipes. Molten Disaster has the benefit of being able to prevent counters, or creatures being sac'd in response, which helps justify the RRR cost. Magmaquake was chosen over earthquake because the instant speed is helpful, and we'd rather deal damage to planeswalkers than players. Keep in mind if you have a sword equipped, these won't damage that creature.
Chaos Warp, Scour from Existence, Meteor Golem- These removal spells are great catch-alls. Chaos Warp is a mono-red staple, and for good reason. The other two, while expensive, will kill whatever we need them to, which is especially helpful for pesky enchantments. Meteor Golem has the benefit of being a creature, which makes it easier to recur with Feldon, or a Buried Ruin.
Red Elemental Blast, Pyroblast- What's a control deck without counterspells? They may not be as versatile as your typical counterspell, but they can still perform the most important job for a counterspell: Countering other counterspells. They also have the added bonus of being able to kill blue permanents, whether it's a lab man or a particularly annoying Mind's Desire.
Volcanic Offering- Look! It's like Diaochan's ability, but better!
Unstable Obelisk- I know it looks like a mana rock, and it is. But really, it's here to act as another Meteor Golem effect.
Flametongue Kavu- Mr. 187 himself is still able to kick it with the big boys. It's easy to underestimate how much dies to 4 damage in EDH. It also kills smaller creatures that you might not want your opponents to waste a diaochan trigger on. Also a great reanimation target for Feldon, and given that you're trying to keep the board as clear as possible, a 4/2 with a sword can be a potent threat.
Protection-
Utility-
Big Boys-
Lands-