I can see the Tyranids have been mentioned already, what i whant to add to this is that according to a dev or i think it is the FAQ on the home page the Tyranids will also attack and push hardest on the factions that controls most ground ingame, so if your in that faction you shut have plenty to fight of. Other then that they have stated there will be plenty of PvE content aswell.
Would be cool to see Lictors stalking and attempting to assassinate the highest ranked players on the team with the most ground taken while gaunts and the heavier 'nids batter at their defenses. Another PvE Objective could be killing that Terivgon that keeps spawning Termagants to attack the outpost. Possible other event that is rarer: Trygon/Mawlocs tunnel under the base after prolonged siege, letting the tyranids pop up inside the base for a chance to shatter the defenders and let the others outside rush in. Mostly depends on how many tyranids there would be in an attack, of course. I'm personally hoping for a large bit on the screen at once. Can't be a tyranid swarm when there's only 30 or so!
Well read the Faq on the mainpage they state there that there will be a big difference in howe hard the Tyranids will be attacking the different factions acording to howe mutch they control etc, and besides why only make them anoying, does not really make any sence. Also the Tyranids are a formidable foe and i would not think that making them anoying only would make them Justice.
Just keep in mind that as far as this being a "game" and being about "fun", you have to balance between something being a challenge and just being cheap or overpowered. So creating an environment mechanically that encourages players to be strategic in fighting the Tyranids would be ideal. Say things like, having spawn creatures/nodes that have to be destroyed. Or having primary targets that help control the Tyranids (don't recall what they're called), that if you kill make killing the rest easier or that stuns them all temporarily (which would also be lore accurate). That way, for people who are just killing random 'nids eventually wouldn't be successful, due to them not actively pursuing the "mission objective" of defeating the 'nids. That gives a nid invasion scope, strategy, and balance. I feel like a lot of people are wanting specific things that thematically sound cool, but realistically in a developmental and implementation stand point just would take a ridiculous amount of resources and tech to create.
I'm not a big fan of the idea of having PVP interfering with my "dungeon" runs. It could be cool, but at the same time if I hate trolls so much. I don't have much time to game so when I do I like it to be efficient. Otherwise getting nothing from a long run would be painful.
Then there is a way to remove the other factions. Savijs idea of different Difficulties is good. But to keep in mind: At war, everyone wants to have dem big guns. For the best "Gear" out of a dungeon there should be PvEvP elements. If you die EVERYONE looses his loot. But the opposing factions dont get the loot. Maybe a function "Intercept a Convoi". The Convoi is the victorious group of players? I know, sounds very trolllike, but some kind of this game mode would be nice. Edit: Or you don't loose any loot BUT you have the chance to get a bit more of resources for the faction?
I think they addressed this saying that there are a few different types of dungeons. One inside your own territory where you can't be invaded, one inside contested territory where you could be, and the last inside Tyranid territory where its such a fight for survival that you'd almost welcome the "help" pvpers would offer in their struggle just to reach you.
