In 40 moves, free 7 birds. More than half of the grid is infested with ghosts, and there will be birds spawning from the sides, which can only join the main grid through a row blocked off by ghosts. Therefore, it should be clear that the ghosts should get a move on so we can complete our objective. Keep matching gifts to make the ghosts disappear. Focusing on clearing one entire side will really help with the objective. Be careful though not to have any ghosts stuck beneath birds in those protruding squares at the bottom of the grid. If that happens, you’ll have put a horizontal striped gift in another square in the same row and then activate it. Or use boosters, as soon as enough ghosts are not obstructing the keys, the Grappling Hook is the fastest and easiest way to complete this objective. But where’s the challenge in that?