So, I'm in an apocalypse game. 13000 vs. 13000 points.

Defenders:
1000 points marines, chapter undetermined
3000 points marines or sororitas, not decided yet
3000 points imperial fists
3000 points ultramarines with AM allies
2000 points imperial guard
1000 points fortifications

Attackers:
Special rules: we can not outflank and we can't bring fortifications. We have some other advantages.
3000 points tyranids (me)
3000 points chaos space marines
3000 points dark eldar
1000 points Tau.


Theoretically ,everything is allowed, but I'm reasonably sure there will be few superheavies around, since basically no one has them. The Dark Eldar have one and there's probably one or two on the imperial side.

I don't have any.

What I have is this:

HQ:
1 hive tyrant, no wings (conversion looked better without them, don't judge me)
1 Tervigon
3 Tyrant guard

Elites:
3 Hive guard
1 venomthrope
2 zoanthropes
1 Lictor

Troops:
5 warriors, close combat specced, one big gun
30 hormagaunts
44 termagants, mix of weapons
9 spore mines

Fast:
1 Harpy
1 Hive crone
4 raveners

Support:
1 Carnifex (close combat)
1 Exocrine
1 Trygon (prime)
1 Mawloc


The question becomes: formations? What's available to me? I've looked through Valedor and the Apocalypse rulebook, and there doesn't seem to be much, though I probably have hte option to borrow some models from others.

Endless swarm is an option, with pretty much minimal size units. Alternatively, I could go for the Kraken Tendril Swarm.

If I can borrow a second tyrant, I might go for hte living fortress. Or borrow biovores and go for the sporeswarm brood.

Does anyone have any tips on where else I could look for tyranid options?