Included in this update:
-Added 4 new characters from "Silly Pigeons" manga:
Hoodie Pigeon, Vest Duck,God Pigeon 1 and God Pigeon 2
-Added a new map: Pigeon Building
-Added a new skin collection for every character: Summer
-Added a new soundtrack for main menu
-Changed the interface to fit the Summer update
-Added 2 new accessories
-Added new weapons
both for new characters and for the Summer Collection
1.15 - Summer Update
Source: Steam Community (opens in a new tab)