Thanks to nalanthus for posting this guide !
Although I haven't been able to do Ethereum Prison (which I think this is), I can say with certainty that this guide, minus the first bit about the depleted items, is not about Ogri'la.
I'm only up to friendly with ogri'la so far, so I can only give the progression that far:
1: Get quest from Grok in Shattrath; He sends you to Mog'dorg the Wizened at the Circle of Blood in Blade's Edge.
2: Get 3 quests from Mog'dorg. All quests from Mog'dorg can be "piggybacked" if you're with another group doing them at the same time. After the gronn are dead, the items you need for quest completion will be laying on the ground nearby for anyone to pick up.
- Grulloc Has Two Skulls: Blade's Edge, near the circle of blood
- Maggoc's Treasure Chest: Blade's Edge, patrols up and down Razor Ridge in the east
- Even Gronn Have Standards: Above Shattrath in the revamped Barrier Hills
3: After those 3 quests are finished, Mog'dorg gives another quest, Grim(oire) Business. It takes 5 people standing in the circles surrounding the rune in order to summon the mob. When he dies he drops a grimoire that anyone can pick up. A note to spectators though, he does a "shadowbolt whirl" that hits anyone in a pretty substantial area for ~3000 damage. I was flying in the area watching those that preceded us while my group caught up, and I was killed in the air, unable to reach my corpse.
4: Another quest from Mog'dorg; Into The Soulgrinder. Once the event is started, you have to fight off waves of ghosts until your target is pulled into the world. You'll start with one beam, it will split into four, until they all disappear and the beam focuses on the gronn and he becomes targetable. Once again, when he dies he'll drop an item that anyone can pick up for the quest.
5: When the last quest is turned in, Mog'dorg will give a yell, announcing you as the new King/Queen of the ogres. You're then (finally) sent to Ogri'la to continue your journey.
6: Chu'a'lor gives you some quests.
- The Crystals: Collect 5 Apexis Shards
- An Apexis Relic: Use 1 Apexis Shard to activate an Apexis Relic and play a quick memory game (think Simon). After a few successful rounds you'll get a speed-increasing buff which allows you to complete the quest.
- The Relic's Emanation (Daily Quest): Go back to the Apexis Relic and play the memory game for longer than before. The second buff you get allows you to finish this quest.
7: Torkus now offers quests.
- Our Boy Wants To Be A Skyguard Ranger: Collect 10 Apexis Shards and take them to either Forge Camp in the area, being careful of the flak cannons if you're flying. In the center of the camps is a forge you can use to trade your shards for an Unstable Flask of the Beast.
- A Father's Duty: Collect 10 more Apexis Shards and take them to Bash'ir Landing. In the northeast area of the landing is another forge where you can trade your shards for an Unstable Flask of the Sorcerer.
8: Chu'a'lor now offers a quest sending you to the nearby Skyguard Outpost, where you can find a few more quests. Some of these give rep for both the Skyguard and Ogri'la, some only give Skyguard rep.
- Bombing Run: You get bombs that can be dropped from your own mount/flight form. Take these to either forge camp and drop them on the cannonball stacks which are thankfully marked, Hunter's Mark style. Once you finish this you get access to Bomb Them Again!, which is a daily quest doing the same thing you just did.
- Wrangle Some Aether Rays!: Go in the nearby area and attack Aether Rays. When they reach low health (>20%) they'll emote that they're ready to be wrangled. Use the rope in your inventory on them and they'll be leashed to you. You don't have to take them back to the Outpost, but you might want to to get them off your back. Once you've wrangled 5, you get access to a daily quest to do it over again, Wrangle More Aether Rays!
9: You know have access to a new group quest at the outpost, as well as 2 at Ogri'la.
- Chu'a'lor gives Guardian of the Monument: 35 Apexis Shards are required to activate the Apexis Monument, which is the larger stone near the Apexis Relic you used earlier. Due to the speed debuff you get when using the Relic/Monument, this quest requires 4 people to complete. You have to play the memory game again, with one person standing on each color. After playing a few rounds, the Apexis Guardian will be summoned. He's a mountain giant that thankfully doesn't split into shards. He dropped a green item and a single Apexis Crystal for my group.
- Gahk gives the quest A Fel Whip For Gahk: I haven't completed this quest yet, but I've been told it takes 35 Apexis Shards to summon each of the mobs Gahk asks you to.
- Sky Commander Keller at the Outpost gives the quest To Rule The Skies: It takes 35 Apexis Shards to break the dragon eggs. All of the dragons have the Bellowing Roar ability, as well as an additional one unique to each dragon. Each dragon also drops a blue scale. If you collect all 4 of these scales you can combine them into a blue level 70 cloak, Deathwing Brood Cloak of the
. I got Hierophant, with 22sta/14spi/40healing. These cloaks are soulbound, but they can be turned into Sky Commander Keller in exchange for an Apexis Crystal.
That's as far as I know, hope it helps!