Formations

[Fishean]

Can a unit be in more than one formations.
Specifically I have the Grukk's Rippin' Krew formation for the deep strike special rule,but I also want to use the Ork Warband formation but don't want to buy more Gretchin so could they be in both?
Another question I have is do the formations prevent it from being unbound or is it still unbound regardless?

[sebi81]

Every unit can only be part of one formation. And a unit in a formation can not be in another detachment.

If all units in your army belong to detachments or formations (which are their own detachments actually) the army is battleforged.

[Charistoph]

Every unit can only be part of one formation. And a unit in a formation can not be in another detachment.

Indeed, it applies to any type of detachment, not just Formations.

Situations like the Decurion and Eldar Warhosts are a little funny in that the Formations are just used to define these detachments rather than being actually IN those Formations.