Black pearls are a currency used to buy hats for your birds. You can get black pearls as rewards in the game, in the Tower of Fortune or Daily Deals. Hats give an additional power boost to your birds and the more expensive hats give the higher boost.
When you collect all of the hats from the same set, your slingshot is upgraded and it also gives a higher power boost to your overall score.
Even if you have a very valuable hat set, it is worth going back to purchase those cheaper hat sets to boost your slingshot: all sets give the same amount of boost to the slingshot, despite the rarity.
How do hats work?
On top of making your bird look super cool your hats also give them a valuable Power bonus. When you unlock a Hat from a higher Rank its power is automatically applied to your current level, so your birdie doesn't have to wear it all the time to get this bonus. You can change hats as often as you'd like, only the highest Power bonus will be counted in your Bird Power. Play around and give your bird a fresh look every now and then!
How do I equip a hat?
To equip a hat after you've acquired it just head to your Hat Shop and find it in the Hat Set it belongs to. There you can pick the hat you want your bird to wear and tap the "Equip" button. That's it! Your bird is now showcasing its fashionable flair for everyone to see 🧢🕊️
Why can't I upgrade my hats anymore?
The only hats that can be updated are the Mighty Eagle Bootcamp hats and special Event hats. The hats you get during special Hat events can only be upgraded in the Event shop, so make sure to do it while the event is still on. And the Mighty Eagle Bootcamp hats are upgraded in the Hat shop, but you can only upgrade them to the 3rd tier after the whole set is upgraded to the second tier.