OK, as I've got no tyranid models yet, all i can do is look at rules. A couple of other things I've noticed in the epicuk rules.

Support Formations. I know it's daft- but it lists a Nest Swarm, consisting of a Synapse Node. Going by the army list, there is no Synapse node. There's a Hive nest which I'm sure is what is supposed to be the option, but I think a name change should just reinforce this.

I can't ge over how good raveners are. I don't have any Carnifex units (they seem to be pricey to buy) but then I think "why bother with a Carnifex?" the reaveners are as good in combat as a Carnifex and what they lose in survivability they make up for in speed (infiltrate and teleport) And they are only 35pts as opposed to 50pts.

Obviously these are only observations (gaming always shows up different things) but I can't help think that either the Carnifex is missing something (mabe fearless?) and/or the raveners are too good (take off MW attacks).

I know the Heirodule and Heirophant are cheap - but they are somewhat uninspiring. I'd have liked a more 'scarey' titan. Especially since with such comparatively weak stats (to other titans) means you can take up to 4 in a swarm - but the models cost up to £70 !!!! No way I'm having more than 1.
Also, Why does Heirophant get synapse and Heirodule not?

Is there no way of having more than 1 trygon in a formation? I would have thought that they would look good in a super heavy type formation of 3. Is it because of the infiltrate rule?