For a persistent energy cost, it can provide significant cover for any unit or structure within range. It is rather inexpensive, costing only a small fraction of the immobile version. It is, however, extremely vulnerable to any unit that can get under its shield or at any time its shield is broken or turned off. The Asylum can also float over water allowing it to use its shield to defend naval units. It can protect against any kind of weapon, including Torpedoes.