Angry Birds 2/Extra Birds

What are the Extra Birds?
Have you noticed the question mark next to Terence? Tap it and you will see we have made space to expand your flock!

To unlock the extra birds, you need to collect special keys available on the map. Remember that player can only be selected once.

The extra birds behave a bit different from the usual flock:


 * They get unlocked by special keys. Just like the rest of the flock, you can find the keys in the level map and choose which bird to unlock.
 * They don’t have hats. Because of this, their card power is determined by the bird's level as well as the hatchling and slingshot level.

In the older version, the extra birds will join your flock in 4 hours and then gone sleep in 9 hours. To pick an extra bird, player must select the bird is expired sleeping time and then press Pick!, simultaneously the play time will run. If one of four birds are sleeping, player will wait and choose another birds to join, or pay gems from the birds are sleeping to join now. Remember that the birds are only playable when the play time is still available and will expire when the play time ends, simultaneously the sleeping time will run.

In the newer version, the extra birds are differently. One of four birds will be still playable without sleeping.