Welcome to the world of Grixis, traveler. Here you will find no happiness. There is only pain, suffering, and death. The fear of suffering is what drives all people. It is why they do what they do. So to control that fear means you control the people who are affected by it. In this idea, you shall find strength. I shall lend you my best spells to help you get acquainted.
Death
Death is the ultimate end. Everyone meets it. It is the job of a good Grixis mage to simply guide his foes to their ending a little sooner than they expect. Because of this, I have supplied you with the necessary spells to show your enemies what it means to control this powerful weapon; the ultimate end. In the pack I have generously supplied to you, you will find such tools of death and destruction like Dreadbore, Cruel Ultimatum, and Cyclonic Rift. Use weapons like these to cleave a path to your enemy, or simply use them as weapons of intimidation. Hold them in your hand, and strike fear into the hearts of your enemies that you might use these tools against them.
Torture
Of course, it is not simply enough to kill. To a proper Grixis mage, the path to death is an art. It is therefore a great honor to give our opponents the most artistically expressionate death they can imagine. Because of this, I have supplied you with an abundance of painful cards, that the screams of your enemies shall be your herald, and their agony shall be your victory.
Look in your pack for cards like Fevered Visions, Fate Unraveler, Niv-Mizzet, the Firemind, Runeflare Trap, and an abundance of other cards that will allow your opponents to gorge themselves upon their own greed of spells, and allow you to punish them for such avarice.
On top of this, I have also lent you the aid of one of my most faithful commanders, Nekusar, the Mindrazer. He is a powerfrul Grixis spellcaster, and a pain artist in his own rite. He shall follow your every order, and will guide you in the arts of torture and death. You may wish to equip him with Phyresis or Corrupted Conscience to make his power even more potent against your enemies.
Chaos
Of course, a clever spellcaster may also be prepared to face against you, in his own rite. Thus, a Grixis mage should always have a little bit of home with him. Not many people can withstand the chaos and destruction of the Grixis homeland, and thus it is to your advantage to use that power against them. I have given you a few of my most powerful spells that will have other mages sobbing on their knees in confusion as their most meticulously laid plans come crumbling down around them, and their most powerful creatures wither away to nothing. Some of these spells are Reforge the Soul, Cyclonic Rift, Burning Inquiry, and Illusionist's Gambit, along with many others. Use these to insight fear into your foes and cast them to destroy any plans they may have against you.
Attack
Of course, there may come a time when you still need to do less-subtle things such as attack an enemy directly, for not every battle goes as planned. I have therefore given you the ability to summon some of the most terrifying creatures known to exist on Grixis. Use them at your disgression to either threaten, defend you, or strike your enemies down. A few notable figures are Consuming Aberration, Thraximundar, and Chasm Skulker.
Protection
For the most part, a Grixis mage does not want to be on the front lines. A good mage would much prefer to be safely casting potent spells from the shadows, and only revealing themselves when it is absolutely necessary. There are a few spells in this pack, then, that should help keep your enemies at bay, and thus let you more easily protect yourselves and deter others from attacking you. Take a look at Illusionist's Gambit, Crawlspace, and Sudden Spoiling to help you protect against the forces of evil. Don't forget that an enemy's fear can be used as a shield for you as well. Do not be afraid to bluff your way out of situations or threaten them with your reputation as a powerful mage. Also suggesting that there are more potent threats besides you, if you happen to be facing multiple opponents at once, is a valid strategy as well. Whatever it takes for you to stay safe is what you must do.
Now that I have gone over the basics of your tools, it is up to you, Grixis mage, to use these tools to the best you can to make a name for yourself, and to prove once and for all that your power should never be trifled with. Make the world shake at the mention of your name, and bring power and victory back to the Grixis banner! Now go! And destroy those who would dare oppose the powers of Grixis!