Leak Year

Leak Year is the first stage in Never Not Summer!.

Battleground
The level starts off with Those Guys, which spawn every 6~12 seconds. A few seconds later, a Celeboodle is spawned. The boss, Selena, comes out when the enemy base is attacked alongside a Bearkini.

Reference

 * http://battlecats-db.com/stage/s01166.html