In 45 moves, free 6 birds. Begin by making some room for new birds to spawn, then make your way through the obstacles. There are keys that free the birds on every column but of course there are a bunch of Iron and Golden Blockers in between, with all kinds of armor. And if all these obstacles weren’t enough, there are two Tombstones in the very bottom. You can try and keep the Tombstones obstructed by Golden Blockers, yet in grids of this size, good luck in keeping up with all the accidental explosions. An easier way could be keeping simply to one side for as long as possible. Since the objective is to free the birds, you can ignore the ghosts, allowing one or two at the time. Just be careful not to have a bird land over a Tombstone as you might waste a few turns trying to get it free.