Dropped by GW due to faggotry. Being remade by Hawk Wargames for Dropzone Commander due to win.
It is set in the Gothic Sector, bordering the Eye of Terror, where Abaddon has launched his Twelfth Black Crusade in order to obtain the Imperium's Blackstone Fortresses. Don't ask how the Tau are there; Warp storm or some shit should be all the hand wave you need.
Some people still think that BFG is one of the best or at least most fun games that GW have ever made. Particularly assuming you just ignore the Necrons, and everyone playing is faintly competent, much fun can be had by all, doubly so when the optional limit on assault boats is used so that escorts are worth a fuck. Any game that encourages you to plow through the middle of the enemy so that you can shoot all your guns at once has got to be pretty good. Also, the flavor of the game is pretty fucking awesome actually, what with the various planet-demolishing shenanigans and just plain gorgeous rule book.
Also, in the land of 30cm range weapon batteries, it used to be that the man with an unerring ability to guesstimate his Nova Cannons on target was king. Putting the 1cm hole onto a 3cm ship base at 100cm range and straight fucking up a cruiser is just beautiful, though of course that takes a fair amount of skill. Alternatively, this can be achieved by building your own board and making apparently random stars bigger and brighter and knowing the distances between them. In theory this is faggotry, but since not a single fucking person ever built BFG tables except the people that were crazy into it, this counts as homefield advantage, or at least is near-on impossible to spot and as such is not really cheating. And then later rules revisions changed the Nova Cannon rules so that the template scattered instead of having to guess the distance to target (as part of the general change from "guess-range" weapons to scattering between 4th and 5th editions), rendering the whole thing moot.
In general it is outclassed by Battlefleet Neoclassical due to its purposeful use of rich ornamentation, elegant arcades,use of isolated decorative elements and superior shielding and medium range arsenal. When compared to the geometric designs, smooth lines, sparing use of ornamentation and forward acceleration and missile and lance arsenal of Battlefleet Art Deco it is clearly outmatched. Can go toe to toe with Battlefleet Ultra Modernist despite its use of vast fleets of cheaply mass produced fighters and typically can best Battlefleet Romanesque in a straight up shooting fight unless severely outnumbered.
Of course this wouldn't be a GW game without the Imperium being represented. Imperial Navy ships look like giant fucking Vaticans with warp drives and cannons. It is rumored that in the lower decks there's like...villages of lost workers, but nobody gives a shit. According to the rule book they have massive fucking crews and apparently zero actual technology to move shells weighing hundreds of tons into gun breeches and such. The book shows slaves running on massive treadmills to move them about. Wouldn't your navy work better if you used like... machines or something? If only we had a bunch of crazy ass priests who are fucking insane about technology on board to sort that shit out for us! This probably had something to do with with the fluff being from 3rd edition, in which Grimdark levels were at their highest to the point of being retarded.
In general, the Imperials are good at torpedoes and nova cannons and other stuff. They also have 6+ front armor, which isn't that big of a deal, but its nice y'know.
The above statement fails to point out that the Imperial Navy is the most diverse fleet in the game, comprising of no less than six fleet lists and sports more cruiser classes, in every subtype, than any other fleet in the game. You can take Space Marine or some Chaos ships as reserves and sport up to four rerolls (more then any other fleet). Nova cannons are so powerful that it is considered poor gamesmanship to take more than three in a tournament list (1500 points) and most of your basic cruisers can be upgraded to carry them. The six up prow is a huge help since most hurt comes from the front, and it lets you take power rams, a nice but situational point filler. Your average range is 30 cm, and only two basic cruisers can push to 45. Your 60 cm weapons are few and far between.
With all the options in the world, the biggest reason why the navy fails to win many matches is that it is predictable by nature and everyone and their pet otaku has a fleet. Easy to play, a real pain to master.
The Chaos fleet is pretty similar to the Imperial Navy, but emo'd up. They are a bit faster than their corpse-god worshiping counterparts and have the largest selection of ships, making them superior to any other fleet (except sometimes Necrons) if correctly built. For unknown reasons, the Chaos ships look totally different from the Imperial ones, not just Imperial ones with tentacles and spikes and crap. While this obviously helps people tell the ships apart, the explanation of 'Oh they are just old ships' doesn't stand up to more than 8 seconds of scrutiny. They later made some ship that was supposed to be the 'old' Imperial ships that were bastard chimeras of both and they were ugly as all fuck and somewhat terrible, which raises the question of why the Chaos fleet is actually any good.
Chaos is good at having MOAR DAKKA on their ships, and using their speed to rock balls.
The above summary can be best diagnosed as acute butthurt when his favorite navy fleet was kicked over by a chaos player six years younger then he was. Chaos sports the second most diverse fleet in the game with the second highest complexity and ship count. While they lack the strict durability and torpedo numbers of the Navy, they make up for it with absurd firepower, assault boats, better speed and overall better ships for fewer points. As a result they have some of the best ships, point per point, in the game. Your average range is 45 cm with lots of 60 cm options, and a few 30 cm options. They also have a pretty flexible set of upgrades, including putting Chaos Space Marines to improve leadership and boarding.
Where Chaos suffers is their lack of durability to incoming fire and ordnance. You quickly start missing that six up armored prow after you watch your prized Repulsive grand cruiser get erased by a lucky round of fire.
Necrons have like 5 different kinds of ship and according to fluff are fucking nasty to fight. They are also the most powerful fleet, second only to chaos (and only if the Chaos player chooses his ships very wisely, you on the other hand, have light cruisers that can blow apart battleships without a scratch), due to having the only armor saves of the entire game (no joke here) and a shitton of close-ranged weapons, and anyone who thinks they're outrunning you in a straight line had better prepare the lube, thus being unkillable and murder incarnate. The drawback is that if you lose even only one ship, your opponent will gain way more victory points than said ship's point cost, something that can cost you victory if you are careless. There is no defeating a Necron fleet that outnumbers you, not in the fluff, not in the game. They remain OP.
Eldar ships look a lot like their vehicles. With only about six ships in the original rulebook, they were somewhat gimped from the get-go. They have shiny fields of awesome to protect them from lances and the like, but gun batteries fuck them up so hard it's retarded, particularly since they HAVE to dip into battery range to fire (the fields are basically naval-scale holofields which obscure the exact position of the Eldar ships, making them difficult to hit with pinpoint weapons, but doesn't help much against the "spam more dakka" approach to conventional battery gunnery). Also, the cruisers are so frail and lacking in firepower that they're worthless, so they're left with a fleet of escorts. While they're pretty fucking awesome for what they are, they melt when sneezed at, so the Eldar are pretty bad except in specific scenarios that let them abuse the fuck out of their movement rules. If the sunside edge is towards the enemy, you are fucked and there's just no reason to play.
Take the Above, and add in that the Eldar sport the most powerful torpedoes in the game (with reroll to hit, and only being hit by turrets on 6's, which is hands-down the best torpedo in the game. Even considering imperial Vortex torpedoes.) Also, their flyers are ridiculous, with rerolls to hit, and 4+ SAVES for tiny fliers. Also, they have weapons batteries that always get the full shots (unlike all other factions, which only get a fraction of their shots for the final rolling). And also, lances that can hit multiple times with a single lance shot.
Then add in the super awesome Forge World Eldar cruisers, and the fact that the Eldar got a damn battleship in the second release, which has EVERYTHING the Eldar have for weapons. Ridiculous cannons. Powerful multi-hit lances. The nasty torpedoes. And the dangerous as fuck flyers.
To sum it up: Eldar are, together with the Necrons, the best fleets in the game. And this is said a BFG veteran who does not even play Eldar.
The buggers are nasty. Not negotiable.
Between this and canonical stuff like an Eldar Ghost Ship surviving a direct hit from an ancient Ark Mechanicus' secret dark matter cannon and leaving only damaged as described at the end of the book Priest of Mars by Graham McNeill, a battle between an Eldar Eclipse Battleship and Failbaddon's Chaos Spess Mehreen Planetkiller would basically look like this: . Be prepared for some insane cheese, which the Eldar are known for and Chaos Lord FAIL, though admittedly Ganondorf takes this much more gracefully than CERTAIN ARMLESS CHAOS WARMASTERS. I mean really, he'd do so well in 40k or Fantasy as a Chaos Lord, walking around with a Circle of the Ruinous Powers behind his head, being bigger than anyone else, having super heavy armor and giant weapons, manipulating greenskins, employing possessed suits of invincible armor, and a supreme megalomaniac to boot, who nonetheless still gets trounced by two heroic elves (halflings? pointy eared human/dwarfs?) barely half his size, plot after plot, though it is by no means easy. 
The Tau have two choices of fleet. Their initial fleets were composed of refitted modular merchant ships and scout vessels. After getting their shit wrecked, they got together and finally built combat ships. Players have the option of the modular, adjustable, Merchant fleet (boxy) or the efficient, effective Combat fleet (sleek). None of the ships' names are pronounceable. "to pronounce it correctly, I would have to cut out your tongue."
The most effective Tau weapon is (surprise!) missiles. Meaning, torpedoes which can adjust speed and direction, which is unique for standard torpedoes in the game (there are guided torpedoes for the IN, but they can malfunction, and do not have the adjust speed gimmick). Other than that, They have starship-sized Ion cannons (macrobatteries) and massive railguns (lances). The other little gimmick they get is that their bomber flyer, the Manta, gets a 4+ save, simply for being massive as fuck.
The Orks look like the most fun to paint, their ships are ramshackle at best and if you used gum instead of super glue to make them it would probably be more thematically accurate... and gross. In theory their random strength heavy batteries are pretty cool, it turns out that random translates alternately into 'pathetically ineffective whenever it's important' and 'did exactly what any other weapon system would have done' inside the game. However, fleets of ram ships are pretty awesome, because nothing is funnier than ramming the shit out of people.
The Dark Eldar are like the Eldar up to eleven, except you have no battleships. You are pretty much the epitome of glass cannon in this game, you hit hard and move ridiculously fast but if the enemy gets so much as a mean look your way you spontaneously combust. You have exactly two ship choices (a cruiser and an escort), rarely a good sign, although their ships have fully customisable weapon loadouts (unlike most other factions, where each ship has fixed armaments with maybe a couple of options).
Tyranids are extremely deadly at close range, all ships besides the Hive Ship are expendable in the extreme, reasonably durable, and ridiculously deadly at boarding. But oh man are you fucked if your Hive Ship bites the dust. Also everyone who plays them just uses 'nid bits to scratch build their fleet. Unfortunately, the hive mind rules mean that a tyranid player can only control one or 2 ships every turn. The other ships are forced to use an Instinctive Behavior algorithm that acts like basic programing for the ship (although in all likelihood this is what you were going to do anyway). This effectively means that a Tyranid player doesn't actually get to make decisions for his fleet most of the time.
Alternate View Well the control of the ships is based on the number of consecutives succesful leadership tests. So have a lucky hand with LD9 and nothing to worry. Even if you don't, the wonderful Instinctive Behavior will probably guide your ships towards your enemies... or the next planet...
But with that said, bear in mind that the hive has a huge fleet with an incredible amount of ships. Your amount of escorts alone exceeds other fleets by 3 or 4 usually. The bio-enhancements can make them pricy, but not all are needed, since only your super short-ranged battery gunnery (which is tyranid space-puke basically) and your ability to EAT enemy ships will secure you victory. They come in numbers. Bodies over Bullets! In a huge scale...
The Space Marines are essentially the Imperium's mighty glaciers. Just like their ground pounders, except apparently the chapter serfs defend the ship and operate everything. They have armor like the Necrons do on the two ships that aren't just Imperial escorts with a new paint job (you do know that SM have their own escorts?*). Those armored ships also have very powerful short-ranged bombardment cannons that are good, but thankfully aren't common enough to be broken. They excel at boarding and going toe-to-toe with the enemy, like everywhere else. They do this by regular boarding (where they get pretty big bonuses), hit-and-run raids by Thunderhawk (which serve as fighter and assault boat at the same time, while also having a 4+ save due to, you know, big armour and stuff. surprise!), or by simply shooting squads of marines across space into the other ship (e.g., boarding torpedoes). They also can do Terminator teleport attacks when they are close enough. Much hurt to be had.
- After the initial release, which intended that you pay a bit extra to get regular Imperial escort ships with space marine crew, GW released models for actual specific SM escort-class ships. Those looked incredibly goofy, pretty much like beat-up bananas, and the crappy white-ish paintjob they had for the GW site were not really helping either. FW then decided to be awesome, and released better kits for them, which were absolutely beautiful.
The Adeptus Mechanicus are pretty much the Imperial ace custom squadron. They operate Imperial Navy vessels with a shiny paint job and upgrades (offset by higher prices and/or downgrades). Apparently, they use servitor slaves instead of human slaves, and occasionally use auto-loaders. Progress! Get an Explorator ship, which is like an Imperial Capital ship but shinier and goofier.
As mentioned above one of the best ways to make the game more enjoyable is to limit the number of fighters, bombers, and assault boats allowed. This limits the maximum number of these craft to not exceed the number of hangar bays available on the capital ships, rather than the original treatment of the hangars like nonstop factories (which encouraged building up truly gigantic waves of fighters and bombers on your end of the table before sending them across all at once). This prevents the game from devolving into something resembling the sky over Germany circa 1945. Not that there's anything wrong with that.
Battlefleet Gothic on Games Workshop's website -- look under "resources" for the rules.Dead because GeeDubs routinely purges their website.
- Battlefleet Gothic 2010 Compendium, a set of updates made by a bunch of community members who worked with Specialist Games before GW axed it. It includes updates and FAQs to the main rules and all official fleets, plus new fleets for the Imperium (including the Adeptus Mechanicus, the Inquisition, and Rogue Traders), the forces of Chaos, the Eldar, the Orks, and the Tau. You can also get the whole compendium as a complete book from DarkReign.
- Battlefleet Gothic: Revised, an effort to rebuild BFG from the ground up. The original coordinator retired from the project in July 2012 (which is a shame, since he had a slick dev blog), but development is continuing actively at the Specialist-Arms forum.
- Battlefleet Gothic Additional Ships Compendium
- Someone has decided that it is a good idea to make it a videogame. IT'S HAPPENING.