Hircine

Hircine's shrine is south of the Imperial City, near the "The" word in "The Nibenay Valley" on your map. It should be on the same sliver of map as the Arcane University when that landmark is at the top of your map, so it's not a huge journey from there to the shrine.

Hircine is the Daedric god of hunting, apparently, and asks for an appropriate tribute: the pelt of a bear or a wolf. You can find these yourself if you've advanced in level high enough to make these creatures appear, or you can buy one from most of the game's general vendors in the miscellaneous category.

This unicorn is located near Hircine's Shrine, so at least you won't have a long way to walk.

When you make the appropriate offer to Hircine, he'll offer you a task: find him a unicorn's horn. To do so, you'll have to find and kill a unicorn. Awwwww! Well, you don't have to do so if you don't want to. But if you do, the task shouldn't be too hard: the unicorn is located a short distance from the shrine, in Harcane Grove. Approach slowly, on foot, and try to take out any of the Minotaurs on the perimeter of the grove before luring the unicorn to you. Obviously enough, a fight against multiple enemies will be difficult to win, so you'll want to try and get the unicorn to come to you without alerting all of its defenders. If you do happen to have multiple foes to deal with, try luring them back to Hircine's Shrine, where the hunters can help you out by pelting them with arrows.

When you have the unicorn's horn in your possession, return to the shrine and offer it up. Hircine rewards you with the Saviour's Hide, a light armor chestplate with a large Resist Magic enchantment on it.

Malacath

To reach Malacath's shrine, follow the coast to the northwest of Anvil. When you reach the "The" part of "The Gold Coast" on your map, you should see it pop up on your radar; it's just north of that point.

If you speak to Shobob gro-Rugdush at Malacath's shrine, he'll initially be dismissive of you: he, and Malacath, prefers not to deal with non-Orcs. (If you're an Orc, then presumably you'll have no problems getting him to open up.) You'll have to Persuade him to tell you what Malacath wants. When you do, you'll learn that what you need is some Troll Fat. Mmm-mmm. If you haven't seen any trolls lately, check out the Tidewater Cave that you probably cleared out for Nocturnal's quest. It's on the southernmost coastline of the map, to the southeast of Leyawiin. Plenty of trolls to be found there.

How did these guys manage to imprison these ogres, anyway?

Hand the Troll Fat in to Malacath's shrine, he'll tell you of a problem he's having. A nearby nobleman, one Lord Drad, has apparently enslaved some ogres that Malacath is fond of. He wants you to free them from their bonds of oppression. A noble goal.

Proceed to Drad's Estate, which is a short walk from the shrine. If you speak to him, he'll tell you that the ogres are holed up in the Bleak Mine, a bit to the east. The lock should be easy to open, but if you wish, you can find a key on one of the small tables on the ground floor of the building.

Freeing The Ogres

If you head into the Bleak Mine, you'll find plenty of well-equipped Guards, as well as a Guard Captain. Start killing everyone you see, or just pickpocket a Shiny Ogre Cage Key and a Tarnished Ogre Cage Key and sneak past everyone in the area. There are two cages here to open (thus the pair of keys), so get to both of them and free the ogres. If you're overwhelmed by enemies, freeing the ogres will let them come out and play, which entails giving massive beatdowns to all of the guards in the mine.

After the ogres are free, they'll run out to the fields and, since turnabout is fair play, will enslave Lord Drad and make him work the fields outside his estate. Ah, delicious irony! Return to Malacath for your reward: a two-handed hammer with Paralyze and Drain Health enchantments.

Mephala

Mephala's shrine lies in the hills to the northeast of the Imperial City, just to the south of the "ea" in "The Heartlands" on your map. When you approach, one of the disciples there will tell you to bring an offering of nightshade to the shrine between midnight and dawn. Nightshade isn't a particularly common plant, but can be found in some of the cities, including in the Arcane University's garden and behind the Mages Guild of Skingrad.

When you've got the nightshade, bring it to Mephala's shrine after midnight to speak to her. She'll tell you a tale of two happy families in the settlement of Bleaker's Way. She wants the families to go to war, so she tasks you with heading to the settlement, killing the leaders of both families, and planting evidence to implicate each family in the death of the other family's leader. Oh, what a twisted web we weave...

Congratulations, you've started up a new Hatfield-McCoy war.

Head over to Bleaker's Way and start checking out the scene. The two families you want to deal with are the Ulfgars and the Dalvilus, with their leaders being Hrol Ulfgar and Nivan Dalvilu. Speaking to anyone in the town will reveal this information, as well as the fact that Hrol is handy with an axe, while Nivan is a spellcaster of some renown. After learning this, both of them will appear as compass markers on your map, so track them down and check them out.

In order to pull these murders off, you're going to need to have evidence to plant on the corpses. It actually doesn't matter how you wind up killing the two leaders, so long as you can implicate the other clan in the murder. If you poke around Hrol's house, you'll find an Ulfgar Family Ring on the second floor near some tools, while Nivan's home features a Dalvilu Ceremonial Dagger on a table near his bed. You'd be wise to start your murdering and thieving after midnight, when both of the leaders should be alone and asleep in their respective homes.

You should get the jist of this by now; you have to kill both of the leaders, then plant the evidence on their body by placing it there from your inventory. Nivan is the easier kill when he's sleeping; just get a sneak attack on him, then drop the Ulfgar Family Ring onto his body. Hrol likely won't die to a single attack, so you'll probably rack up a bounty while killing him. Regardless, take him out and plant the Ceremonial Dagger on his corpse.

With your work done, tell anyone in the town about the murders, and they'll be triggered into a violent melee right in front of the inn. You can watch if you like, or just head back to Mephala for your reward: the Ebony Blade, which deals an excellent amount of damage, plus has Silence and Absorb Health enchantments on it.