Halloween bats flying with forest

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 digital generated image 3d composite graphics three dimensional white background plain background cut out trees lush foliage boreal forest environmental conservation forest abundance copy space environment woodland mountain silhouette nature 3d digital generated treetop fir tree woods green illustration fir tree branch christmas tree foilage