The Howler is a cautious ghost that floats a few feet above the ground and dig up ghost energy and Blue Spooks every so often. Before entering or leaving a section they will face behind them for a short period of time to ensure they aren't being followed before moving on.
If a Howler spots something it is unsure of it will shriek in terror and flee to a safe spot until it the danger has subsided. During the commotion it can summon Blue Spooks which will promptly attack.
Howlers cannot be captured whilst moving or awake but can be captured when they rest at their nests.