Welcome to Exploit Week here at DailyMTG! During our time with Dragons of Tarkir, exploit, to the casual crowd, generally means Sidisi, Undead Vizier. No card with exploit catches the imagination quite like Sidisi. I mean…really, sacrifice a creature that you probably don't care about to Diabolic Tutor for a card?
Consider the difference between Sidisi, Undead Vizier and Diabolic Tutor. Sidisi costs five mana and the sacrifice of a creature to get a 4/6 deathtouch creature and any other card in your library. Diabolic Tutor costs four mana. Remove the Diabolic Tutor cost from Sidisi and for only one more mana and a creature you get a 4/6 deathtouch creature?
This card is outrageously good. Unless you aren't running cards that tutor, if you have black and creatures in your Commander deck, this card is dangerously close to "auto-include" status. I am tempted to run four in a 60-card deck and use the first to search out the next, then the next, then the next! I can't recommend this card enough.
However, I'm not going to spend the entire article talking about the exploit cards in Dragons of Tarkir. I want to look at the bigger picture: the role of exploitation in your games.
Becoming Adroit with Exploit
Most players use some exploitation in their multiplayer games, but they don't call it that. Exploitation has negative connotations that suggest it wouldn't make sense in game environment. Pimps and sweatshop bosses exploit, not Magic players. Realistically, though, have you ever put a player into a situation where they were forced to help you, even though it wasn't really in their best interest? Have you ever taken advantage of a situation in a game where Brian was forced to deal with another opponent's creature that was threatening both of you? Have you ever considered countering a card, but knew it would hurt Dirk so much more that he would have to counter it if you didn't, so you let it fall to Dirk to counter? Looks like we both have something in common with pimps and sweatshop bosses.
But keep your chin up! While the sweatshop boss is practically killing his employees to make a buck, your motives are much more benign. Players tend to exploit other players as a way to protect their resources. If you can convince another player to attack an opponent, rather than doing it yourself, you've protected your resources. The attacking player could lose their creature, be unable to block later on, or draw the ire of the opponent they chose to attack. Those are all risks that you don't have to take because someone else is doing what you were going to do, but now no longer have to. You have saved your resources (permanents, life totals, etc.) and left someone else to do your work!
Exploiting an opponent isn't limited to having them attack someone else. If Mike removes an annoying permanent from the game, you have saved your removal for another permanent. Any way you can save your resources (or grow them faster than before), by finding others to do your bidding is beneficial. Exploiting an opponent to get that advantage focuses on the position of your opponent. If you can convince your opponent to do something because of your silver-tongued oratory, good for you, but that is not necessarily exploitation, so much as masterful politicking. Exploitation involves taking advantage of an opponent's vulnerable position to get them to do your bidding. You don't need to be silver-tongued for this to work, you just need to be able to identify (or create!) the situation and use it.
Identification of an Exploitation Situation
The ability to identify opportunities to exploit your opponents before they come up is essential. This will give you the chance to better position yourself to take advantage of these opportunities and be aware of those other times when it will fall to you to get the job done. In the early part of a game you find yourself being attacked by a 2/2 Solemn Simulacrum. You have your own 2/2 creature to block, but you are questioning whether you should. If you know that future attacks will likely go against other opponents, you may opt to lose the life and let the other players use their resources to deal with the Simulacrum. You'll know when this makes sense based on players' decks and the play through the course of the game.
Each player's deck has some plan of attack. Whether they're burning someone's face, rushing with smaller creatures, setting up a pillow fort, or building their mana base for the late game, everyone's deck has a plan of attack. Everyone's plan of attack focuses on giving them an advantage over the others in some aspect of the game. This is almost invariably done by allowing for a weakness in another part of the game, with the hope that the advantage in one area will limit the weakness in another. Great decks tend to have some way to handle the weak points, but it tends to force them to react in a certain way. In looking at the weaknesses, or the limitations in how a deck can protect those weaknesses, you can find ways to exploit them.
During some games, your opponent's plan of attack can run into some immediate / short-term issues. For example, when a deck is designed to use the early game to build a mana base, but the opponent, Chewie, is forced to shift gears because you and Chewie are being pressured early by a rush of creatures from Bill, there is an opportunity to exploit. One of you will have to deal with the threat or you'll both die. If Chewie is at 5 life, while you are at 12, you can afford to wait, since you know Chewie must respond first or die.
Your opponents can run into long-term issues with their plan of attack as well. If Erin is ramping her mana to be able to afford to play bigger creatures but Hallie has played Knowledge Pool, Erin has a long term issue with her plan of attack. Erin's deck can still work, but not nearly as well since she was hoping to take advantage of her ability to cast more spells than others. With that advantage gone, Erin needs to deal with Hallie's Knowledge Pool more than you do. This is a situation where Erin can be exploited. Forcing her to burn up resources to get rid of the Knowledge Pool while you accumulate resources or take advantage of the Knowledge Pool, knowing it is hurting you far less than Erin.
You can even exploit your metagame. Many years ago I played in a group that didn't use many enchantments, but everyone ran Naturalize or some variant to deal with artifacts. I regularly built decks that had no way to deal with enchantments, relying on others in the game to handle the few that came up. By exploiting my metagame, I opened up four slots in my deck for other cards that could better help me win the game. Admittedly, I often used those slots for goofy cards that flipped games upside down, but I could have used those slots to improve my deck.
Don't judge me!
The area where you'll most commonly see an opportunity for exploitation lies in the space of mutual concern. When Kate and you share a problem (e.g. Allan has Aura Shards on the battlefield), you are more likely to see opportunities to exploit. Shared problems means that two or more of you are looking for answers, so you can try to exploit the others. If you don't share a problem, your opponents are far less inclined to deal with the issue, since it doesn't hurt them, and you are not gaining anything when an opponent is at risk but you aren't.
When considering Allan's Aura Shards, if I have a face-down Ainok Survivalist, I'll hold off megamorphing it in the hopes someone else (Kate) will deal with the enchantment. I'll be especially persistent if I know Kate is running Krond or enchantment creatures. You expect Kate has ways to deal with a card that would shut her down completely, so you exploit that and hope she deals with the issue before you have to.
Other areas to watch for are situations that are problematic for you but no one else. These are situations where, at best, you have to deal with the problem, and at worst your vulnerability is exploited and you are all but removed from the game. Being aware of these pitfalls is important as you can navigate around them or hold onto the one "out" you have for that situation, no matter how tempting it would be to use it elsewhere. You are looking to exploit others specifically so you have the resources to deal with situations where you are the only one.
A rarer situation lies when you lock down an opponent. I do love a delightful situation where Kriz is under your thumb and you can kill her at your whim. Whether Kriz continues playing because she has a single way to escape your lockdown and is desperately trying to find it, or she is hoping you'll make a mistake and let her up, Kriz is in your back pocket. Exploiting this situation is a game of chicken. Early on, you can force Kriz to do what you want—she has no way to save herself. As time progresses the likelihood that she finds an escape or someone else in the game finds a way to help her out will increase. How long do you exploit before putting Kriz out of the game?
Exploiting for Fun and Profit
The final, and probably most important, question to consider is whether the opponent has anything to offer. Opponents are regularly in vulnerable positions throughout the game. Many of them reached that position because they have no way out. Earlier I used the example Kate running enchantment creatures and Krond in a deck when Allan had Aura Shards on the battlefield. Your ability to exploit that situation depends not only on your ability to be in the position to enjoy a benefit, but also on Kate's ability to get out of the situation. You know Kate needs to respond quickly or she'll find herself sitting on the sidelines, but if she has no way to deal with Aura Shards, how do you exploit her? In that situation, you need to look to Allan. Perhaps you can make it clear to him that he is at risk since Eric's only way out is killing him. Exploit the situation and use your resources elsewhere.
Exploitation is not color- or deck-specific. Every player can and should exploit every situation possible. Winning games requires the most efficient use of your resources and exploiting situations to leave others using up their resources is just sound game play. Take advantage of the situations presented to you and enjoy your Magical exploits!
 A “tutor” is any card that lets you search for other cards in your library. Many early cards that did this included “Tutor” in their name. Demonic Tutor, Diabolic Tutor, Enlightened Tutor, and Worldly Tutor are a few examples.
 Many players hate that term, myself included. There is a belief that some cards are good enough that they can go in almost any deck, or at least any deck that can run those colors. Sol Ring is a card often described as an auto-include. I like to think that there is such variety in decks, that auto-including any card is an insult to deck builders’ ability to find cards that work perfectly in the deck they are building, rather than being forced to fall back on cards that “should” always go in your deck. I use auto-include here to show just how versatile Sidisi is.
 Although if you haven’t figured out which one I think is best, go back to the start of the article and try again.
 "Pillow fort" is a term referring to decks that play endless defenses on the battlefield in an attempt to discourage opponents from attacking them. The player sits in their pillow fort, rarely attacking until only one other player is left. The belief is that the player will be able to stockpile resources for the final battle, while the other players use up their resources to eliminate the other opponents.
 When I find myself on the wrong side of this situation, I tend to immediately push the exploiter to kill me. I don’t wish to be a pawn who just hangs around until I am killed off in the end. If the exploiter is going to win the game, he’ll do it without my help. This is not the best move strategically, but I want my opponents to know that I’ll work with them when we are equal partners, but not as someone who is basically Mindslavered for the rest of the game.