Halloween bats flying with cloudy sky

digital animation montage animation bats flying bat halloween spooky scary autumn background screen october pattern swarm swarming design element danger darkness dark cartoon herd haunted sky monster concept conceptual alpha alpha channel template editable transition alpha matte alpha mask luma transparent background blue cloud white background copy space 3d digital generated illustration graphic nature shape beauty in nature weather cloudy scenic cloudscape night clouds outdoors tranquil scene idyllic environment dramatic sky moody sky overcast tranquility ominous full frame backgrounds flare white glow flash light digital