I might have missed it or just not be in the right thread, but does anyone know if there will be playable nids added later on?

probably not, they have said they are an NPC species only i believe (i may be wrong)

Thanks mate, good to have at least some idea and not get my hopes up and then be disappointed with an awesome game

Yes. If players are really playing badly enough for it to be possible, we deserve to lose.

this works

Tyranids as a playable faction? Erm...

Technically, the Nids' never lose. The hive fleets are still snaking into the Imperium, and at most victories are short lived as another tendril makes orbit and starts eating everything. The nids' are extremely dangerous, and, in canon, are heading non stop towards the astronomicon...The Golden Throne. So yea, the Nids' can and do win campaigns on a regular basis a win against nids' always comes at a heavy price for Imperial Forces. Exterminatus is actually used a fair amount to stop a tendril fleet, as it starves them of biomass. Sacrifice one planet to save a system ^^

Keep in mind the current hive fleets are basically scout fleets for the main warrior fleet that the Imperium hasn't seen yet.

What this guy said. The nids' so far haven't commited a full force. Ultramar was nearly lost to Hive Fleet Behemoth at the battle of macragge.

Not to mention they can regrow their champions with all previous battle experience.