UPDATE: Blizzard originally bumped up the reputation requirement to 50 but have since reverted it back to the original requirement of 40 reputations. Take your pick of the 50 listed below! =)
Generally speaking, there are a few ways one can grind reputation for a given faction.I've listed them in order my preference - keep in mind that this is personal preference and changes from player to player.
- Quests: By far the easiest and most preferred way of gaining reputation for me. It takes away the grind's tedious aspect, adds to other achievements (Seeker/Loremaster), and gives a decent amount of reputation for easy, often low level quests.
- Dungeons/Raids: Heroics give the most significant amount of reputation here. Dungeons aren't bad if you're able to solo them (as in BC) but they could be time consuming at 85.
- Item Turn-ins: A tedious method but it gets the job done and the best part is you can power through these kinds of reputation. This depends, however, on whether you can speed it up by buying the items off the Auction House or whether they are BoP and must be farmed out.
- Dailies: Ugh. My least favourite kind. Dailies and I never get along simply because it makes me feel like Bill Murray in Ground Hog Day...I return every day to do the exact same quest since despite my efforts they always need the exact same thing. *Shudder*
- PvP: This probably wouldn't be all the way down here if I were actually good at it. Sadly, I am not and so at the bottom it stays.
Note: Any reference to the amount of reputation gained does not take into account guild bonuses or racial bonuses.
The capital cities reputation (with the exception of Gilneas) can be easily obtained by completing the low level questlines from their respective starting zones. Although they now offer tabards for championing their cause in dungeons, I highly recommend questing over dungeons for these.
- Tranquilien (Horde-only)
There are two kinds here - the ones where the dungeon mobs give you reputation and the other where you have to championing the faction in a dungeon.
Mobs that give reputation:
- Honor Hold/Thrallmar: Initial questing should get you to honoured after which heroics are the next best option. All the heroics in Hellfire Citadel (Shattered Halls, Ramparts and Blood Furnace) grant reputation. These heroics are unlocked with the Flamewrought Key and the Shattered Halls Key - sold by the Honor Hold quartermaster. There is a PvP daily available but with the content outdated, heroics are the better bet.
- Lower City: Your best bet is to complete the quests and grind normal dungeons all the way until honoured for the keys to unlock the heroics. And then continue merrily on in the heroics of Auchindoun (Shadow Labyrinth, Sethekk Halls, and Auchenai Crypts). The good news is that you have a chance for the rare mount from Anzu in Sethekk Halls as a perk to your grinding efforts!
- The Sha'tar: There are only a few quests for this faction so its worth finishing all of them. You can get reputation until honoured while turning in items for Aldor and Scryers which works out since its two birds with one stone. After honoured, your choice of heroics are Mechanar, Alcatraz, and the Botanica.
- The Violet Eye: Simple and easy - the mobs in Karazhan give reputation from neutral to exalted. There used to be a questline as well - I'm not sure if thats changed with Cataclysm or not. I will update that when I can.
- Ashtongue Deathsworn: The faction with the coolest name. *Cough* This faction's reputation begins with the questline in Shadowmoon Valley from Elder Sage Akama with the quest Akama. Following this, grinding mobs in Black Temple is the path to exalted. You can choose to either clear the entire raid (gives ~8k rep) with a friend or ignore the bosses and simply work on the trash. Easily doable with a few friends at 85.
- Hydraxian Waterlords: Molten Core is the weekly hangout for this. The trash in Molten Core grants reputation until revered and then no more. The journey from Revered to Exalted is filled with the mean bosses of Molten Core who are soloable, or at the very least two-mannable.
- Brood of Nozdormu: There used to be a quest chain for this which has now disappeared with the Shattering. One starts out at hostile and must work up to Exalted by farming Ahn'Qiraj. A cool name but truly one of the more trying reputations.
- The Ashen Verdict: All mobs in the Icecrown Citadel raid grant reputation towards this faction. Grab your friends and get farming!
- Keepers of Time: Durnholde Keep and Black Morass instances are your two sources for reputation.
- The Scale of the Sands: Reputation for this faction is gained through farming the raid Mount Hyjal, which can be accessed in the Caverns of Time.
- Gilneas: I got this one almost solely with championing in 85 heroics. A quick way to add some rep is to do the quests offered in Shadowfang Keep.
- Guardians of Hyjal: Questing in Mount Hyjal gets you all the way to revered, which I highly recommend. After that, its championing for the final lap.
- Ramkahen: Completing the normal quests got me to honoured after which I hugged the tabard as usual.
- Earthen Ring: Their quests are spread out in Vash'jir and Twilight Highlands. Championing is the sure and easy way to go once the quests are completed.
- Kirin Tor: The questline gets you to friendly after which championing is the way to go.
- Timbermaw Hold: The initial questline for Timbermaw starts at Emerald Sanctuary and it is worth doing them since they award a signficant amount of reputation and get you to honoured. Past that, farming the Deadpaw or Winterfall mobs and turning in feathers or spirit beads gets you to exalted. Save your items until you've maxed out honoured since mobs will no longer grant reputation beyond that.
- Sporegarr: After completing the quests, the easiest way to gain reputation with this faction is to turn in Sanguine Hibiscus. These are not BoP and can be purchased on the Auction House. Alternatively, one can do the repeatable quest Now That We're Friends...
- Kurenai: Completing all the quests in Nagrand should get you revered with this faction. Following that, you're best bet is to kill Ogres in Nagrand which drop Obsidian Warbeads which can be turned in at stacks of 10 for reputation.
- Consortium: There are a couple options for turn ins with these guys. Like Kurenai, they also accept Obsidian Warbeads for reputation, so it'll be a decision as to which faction to turn those into. Alternatively, you can also turn in Zaraxxis Insignias at Area 52 which are easily farmed in Netherstorm. Another great alternative is the Ethereum Prison Key which drops after honoured with Consortium and after completing the quest Seeking out Ameer. These keys allow you to open Ethereum Prisons which grant rep and also give you a Prison I.D Tag which you can turn in at Ameer for rep.
- Cenarion Expedition: After completing the quests, Unidentified Plant Parts can be turned in for rep until honoured. Following this, Coilfang Armaments can be turned in until exalted. Both items are not BoP and can be bought on the auction house from time to time. The Armaments can be farmed from heroics in Coilfang Reservoir (in which case you could combine it with gathering Sanguine Hibiscus). Keep in mind that you need to first complete the quest Orders from Lady Vashj to open up the repeatable Armament turn-in.
- Cenarion Circle: The easiest way to get rep for the circle is to grind out the Twilight mobs in Silithus. The mobs drop Encrypted Twilight Texts that can be turned in for a good chunk of rep while you get a little bit of passive rep simply from the mobs themselves.
- Thorium Brotherhood: This is a relatively easy reputation to get since the Shattering. You can turn in Dark Iron Ores, Fiery Cores, Lava Cores and Core Leather now which grants 2000 rep per turn-in. A handy way to spend all the stuff collected from those Molten Core runs.
- Darkmoon Faire: Befriend a scribe for this one or watch the auction house like a hawk. Reputation with this faction is primarily gained by turning Decks such as the Mages Deck or the more rare Tsunami Deck. Normal decks grant 25 reputation while rare decks grant 350 reputation.
- Aldor/Scryer: Turn in Firewing Signets/Mark of Kil'jaeden until honoured (and you also get the passive Sha'tar rep while doing this). After honoured, complete the quests offered by these factions both in Terrokkar as well as Shadowmoon Valley and turn in a combination of Arcane Tome/Fel Armament or Sunfury Signet/Mark of Sargeras until exalted.
- Explorer's League: Their base is in Howling Fjord where they offer a daily at the Steel Gate. Alternatively, running Wrath heroics with no tabard equipped gives reputation to this faction.
- The Frostborn: The easiest way is the one above - running Wrath heroics with no tabard equipped defaults to the four reputation under the Alliance Vanguard.
- Shattered Sun Offensive: Many of their dailies are in the Isle of Quel'Danas with a couple available from Shattrath. You could also throw in heroic Magister's Terrace to bolster the rep gained per day.
- Silver Covenant: All the dailies in the Argent Tournament award reputation. Alternatively, running any of the Wrath heroics without a tabard on awards reputation as well.
- Alliance Vanguard: Is really the combined faction of The Frostborn, Explorer's League, The Silver Covenant and Valiance Expedition. Reputation gains for this one are passive since gaining reputation for any of the four factions adds reputation to this one as well. It does, however, count as a reputation for the achievement.
- Wildhammer Clan: The questline in Twilight Highlands come highly recommended after which many of the normal quests turn into some easy dailies.
- Baradin's Wardens: These dailies are located in Tol Barad and are the only way to gain reputation with them. Le sigh. The total number of dailies doable is 18, depending on whether your faction controls Tol Barad or not.
- Ogri'la: Completing the questline that makes you queen of the ogres should get you to friendly or close. After that it's the long road of hardmode memory games to gain reputation with these folk.
- Shatari Skyguard: Located right next to the Ogres, the dailies open up after you do the breadcrumb quest for this faction in Shattrath.
- Knights of the Ebon Blade: Based in Icecrown in the Shadow Vault, completing the initial questline and phased content will open up various dailies. Alternatively, they can be championed.
- Therazane: Completing the initial questline in Deepholm will get you from Hated to Honoured where dailies will open up for further reputation. Hitting revered will open up additional dailies. Alternatively, you can champion in a dungeon but the dailies do offer some neat achievements and rewards such as Pebble.
- Netherwing: After completing the initial questline from Mordenai and going from Hated to Neutral, dailies open up at the Netherwing Ledge. Note that at each reputation tier, new quests and dailies open up so keep an eye out.
- Argent Crusade: After completing the normal quests, they offer dailies spread out in their various bases of Zul'drak, Icecrown, and the Argent Tournament.
- Wyrmrest Accord: In addition to the normal quests, dailies open up at the temple with an achievement for one of them. Alternatively, championing the tabard works too.
- Oracles/Frenzyheart: Dailies available in Sholazaar Basin once the initial questline of A Hero's Burden is complete.
- Kalu'ak: There are three dailies total - one at each hub of the Kal'uak in Northrend. Doing the normal quests can get you to revered after which the dailies give additional reputation.
- Sons of Hodir: The questline beginning with They Took Our Men! opens up this faction. Once honoured, the giants offer various dailies for reputation. To speed things up, Justice Points can be turned in for Hodir rep tokens as well.
- Argent Dawn: With the Shattering, the Argent Dawn has now reverted to dailies for reputation. In order to unlock the dailies, follow the questline beginning with Fiona at the border of Easter Plaguelands and Western Plaguelands.
This one really needs no explanation. It is the slow path of winning battlegrounds.
- League of Arathor
- Stormpike Guard
- Silverwing Sentinels
Of Special Note Are...
At this point, I've thought of all non-crazy factions I can think of and the total number of reputations is at.... 50! You'll notice I still haven't included the Steamwheedle Cartel since the Shattering took away many of the repeatable quests in Dire Maul and Ferelas. It is still possible to get reputation with them but it seems to be a lot harder than it was before (never thought I'd be saying that but there you go!) That said, there are two important factions that need special note while we're doing the count:
Wintersaber Trainers: This is probably the most grindy reputation I can think of and it certainly survived the Cataclysm. There has been buzz on WoW Insider about the Wintersaber mount being obtained by dailies instead of a reputation grind in Patch 4.1 - more in line with its Horde equivalent. The good news is that the mount will be much easier to get. The bad news is the faction will most probably become a Feat of Strength like Zandalar and Shendralar reputations. Not great if I'm trying to avoid those tedious PvP reputations so I'll probably grind this one out before the patch hits.
Guild Reputation: Interestingly, this is just like any other faction and counts towards all reputation achievements.
Remember, this is not counting factions that have been removed from the game but still count such as the Zandalar Tribe. Maybe I can one of those darned PvP factions afterall! I'd say that this achievement is very possible without having to go the way of "insane" reputation grinds such as Bloodsail Buccaneers or Ravenholdt, or even the Cataclysmic Steamwheedle Cartel now. It is by no means easy and the key is to space it out, rotate between the factions and mix things up to keep yourself from going crazy. But it sure isn't impossible, regardless if you happen to have old exalted reputations or not. Thanks for reading and happy reputation hunting! (Wow this turned out to be a really long post....)