The unlock conditions for the mysterious Characters in Shooty Skies were always quite hard to figure out. In the last version the unlock of the Drama Llama was a big mystery that could finally be figured out. In addition there was a bug preventing the player to unlock more then one secret character at a time, that was fixed by an additional update.
The new secret pilots in the Shooty Skies Black Friday Update are Roddy Cat and Monster Savings.
To unlock Roddy Cat play with Rowdy Cat and shoot down at least 50 Shopping Carts.
The unlock conditions of Monster Savings are not exactly known so far. Some people unlocked him by playing with Bargain Hunter and collecting more than 100 coins (between 300 and 500 coins?) Others report that a highscore is needed in addition to that to unlock Monster Savings. We tried the reported conditions and collected more than 100 coins and made a highscore in one run, but did not unlock a new character. If you have more information please write a comment!
Beside the unlocking drama a new Shooty Skies Secret Character Bug was reported for the update. If you can't unlock both characters this might be because of that bug.
Here you will find how to unlock the secret characters from the previous Halloween Update.