Welcome to Librarium Online!
First off, I have only played 1 game on a featureless terrain with 750 points Imperial against 750 points Chaos, and won that game.
Myself, I play 40k Tyranids, and it would seem funny to have a hive fleet to go with them. I browsed through their rules and stuff, and my eye fell on the following:
You can field about 30 Kraken with Gigantic Maws and a few with Feeder Tendrils (this for inflicting criticals on ships, and easily killing escorts because of that). I wondered if this fleet would be any good (it is supposed for 1000 points). I thougt the maneuvabilty and toughness of the kraken would give some fun. I guess you probably outnumber your opponent with these "ships" and still have a good bite, by concentrating your 'melee' attacks at big ships. Shield are no problem, because Maws and Tendrils ignore those.
How do you think about this?
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You're describing the Vanguard list if I'm recalling right.
It is just fine, and indeed is one of the few times GW actually encourages an all escort list at 1k+ point values. (if I recall the recommended size is 1.5K for the campaigns the list was themed around, since it counts as a raiding fleet list).
I say if you like, go for it.
Yeah, it does sound like a fun list to field. It would be completely legal and completely different from the type of fleets most people have had to face. Your lack of ranged weaponry might leave you at a disadvantage against faster moving opponents, but the sheer number of vessels you will be able to field will help to compensate for this.
I'm not sure how well a fleet like this would perform in a competitive match (it could go either way really), but I'm sure it would provide an interesting and amusing gaming experience. As I said fast fleets, like the Eldar, would be difficult to get close enough to to do damage, so be careful there. You will be taking fire long before you could deliver damage yourself against any fleet. However, as Kraken are very durable (!) and you will have quite a few of them the fleet could work very well. It might be an idea to throw in a few ranged ones to give the fleet some flexibility, but this is up to you.
If you like the idea mate, I suggest you go for it and have as much fun as you can. Good luck!
I've been playing BFG tyranids for just under a year now so I'm pretty comfortable in saying that yes you can be very effective with a list like that. A couple of warnings though. Biggest one is if you generate your terrain as per the book be very very careful about solar flares. all it takes is one pulse acroos the board and poof there goes half your fleet. With out any shields at all those area effect, deals one hit to everything weapons/effects can really really ruin your day. Taking some vanguards might be a good idea just you have something to fall back on in case the worse occurs.
Beyond that kind of weapon you are extremely tough however so enjoy it. Also when using that many close combat weapons don't be afraid to follow up with some boarding actions as well since your in that range. Doubling your boarding value makes squadrons of kraken deadly in this regard, landing a few hits with claws to soften them up a bit then follow up with boarding. You'll probably lose a ship or two to the retalitory crits but its almost always fatal to anything cruiser class. I've even managed to drop battleships, but thats takes either some really lucky rolling or combined squad efforts. Its definatly alot of fun though. Especially in the Vanguard list where you'll want to have high squad numbers to keep leadership up. Anyway I think I've rambled on enough here so I'll stop with this. Welcome to tyranids BFG. Go eat some space marines (they crunch very nicely!)