Plasma mortar

The Plasma Mortar is the primary weapon of the Wraith and the Covenant Air Artillery.

Introduction
The Plasma mortar fires huge ball of slowly moving superheated plasma with a large explosion radius and slow rate of fire. It is extremely powerful, usually kills infantry in a single hit and can destroy just about anything on the battlefield in a minimal amount of shots. Its plasma projectile moves relatively slowly, making it more susceptible to gravity, causing it to fire in an arc, like the Fuel Rod Gun, which allows for it to simply go over obstructions such as barricades and hills.

Tactics

 * A Plasma Mortar fires in an arc so it is somewhat difficult to hit a target. The further away you are, the higher you will have to aim to actually hit the target.
 * Due to its slow-moving nature, the plasma ball will be much easier to avoid than a human projectile.
 * Remember that even if you are behind cover, you may still not be protected from the plasma's curved trajectory.

Covenant Artillery
A giant stationary plasma mortar was seen destroying buildings in the Halo 2 E3 Demo video. Sergeant Banks called in an airstrike and a group of Longsword fighters flew in and destroyed it.