#12 Sleigher – Shooty Skies Secret Character

#12 Sleigher
This character is a tribute to the American thrash metal band from California with the similar name Slayer. To unlock Sleigher choose one of the new Christmas Characters (Shooty Feet, Elfabear, Blitzen, Ho-Ho-Hobot, Hoppy Holiday, Poley) and defeat every Christmas enemy occurring in one round including the Christmas Boss.
It may also be possible that you need to beat round about 3 christmas bosses in different rounds.

#8 Monster Savings – Shooty Skies Secret Character

#8 Monster Savings

The official conditions reported by the developers for unlocking Monster Savings:
Collect at least 500 coins with Bargain Hunter in game. You don't have to collect the coins in one run.

We tried to unlock the character with that conditions, but we were not successful on iOS, but it worked on Android. Most probably there is a bug in the current version. The developers are informed and are working on it.

#5 Drama Llama – Shooty Skies Secret Character

#5 Drama Llama

 First of all unlock Hooty and Blobby. Now you have to get a good or a great score with both of the two characters. A great score is considered to be a high score or a score relatively near your highscore. Once you got it with both characters Drama Llama will be unlocked! This is considered to be "old people's music joke", because there is a 90's music band called Hooty and the Blowfish.

#3 Pew Pew Pew – Shooty Skies Secret Character

#3 Pew Pew Pew

Play as one of characters with a Western / Cowboy background like Prickles, Boomer or Rattles. Play this character for a while and after a while the Shooty Skies mystery character Pew Pew Pew will be unlocked, it's a gun fitting to the western environment. The exact condition is unknown, but this character is rather easy to unlock, just keep playing for 5-15 minutes.