C-3PYOLK (also known as C-3PO Bird) is a protocol droid who is the best friend/translator to R2-D2,
For the player to use the character as best as possible, it's better to make sure that C-3PO is surrounded by as many bricks as possible, and releasing his ability once he is. His ability shouldn't be launched from far distances, as once the pieces lose their speed, they will no longer be as powerful.
C-3PO's ability takes a lot of strategies, just as the original Matilda. If used right, he can do much damage. It can also be noted that unlike the other Angry Birds games, all characters can use their ability even after they hit a structure. (however, this feature will only be available for quite literally only a split second to a second)
C-3PO reappears in this game, with a new design to match his design from the promotional animations. He has the same ability as the original, only that now he is playable in normal gravity levels. (as he was only featured in zero gravity in the first game as a bonus character) Due to this, physics do apply, and the pieces that he splits up in will burst out and then fall to the ground.
The other Silver C-3PO is slightly different. In his ability, he will split into 4, rather than 6, pieces that of course, will be much bigger and denser, making them much better at destroying materials and structures. However, the original is much more versatile, so it depends on the player's choice. If the player wants something more destructive for point value or just to beat the level, then the silver version is preferred. If the player, however, wants to hit multiple targets at the same time, then the original may be more preferable.