Banisher Is a heavy missile tank. Its homing missiles have a long range and deal massive (1000) area (128) damage to both land and air targets, but with a long reload time that leaves them open to counterattack.

A good hard-counter for the Hound, since it cannot dodge the missile. Banishers can also soften up units that may outrun your supporting army, like the fast Jaguars.

The Banisher is also a flexible AA unit. It kills most T2 threats like Roughnecks, Stiletto & Liche in 2-3 shots, though it's important to point out that:

The Banisher prioritizes targeting ground units first.

Its slow turning speed can easily get it killed. When moving into range, remember to keep its broadside facing the enemy so it can turn around and run. Use sparingly as a first strike unit for a devastating opening punch.

Never rely on Banishers alone, and always support them with other forces.