More Dakka-This is tricky.  Most of the species involved in the whole Equestriaverse are not into the whole “leave a huge smoldering crater where your enemy once was” theory of combat.  Too messy, wasteful, etc, etc, etc.

But.

But, sometimes, you just have to kill everything in sight and they have quite a few ways of doing this.  The first is gravity guns-think “magnetic coil gun, but using tractor beam technology”.  Most suits of powered armor mount two of these, with independent targeting systems and all the accessories to allow you to aim a 5mm projectile moving at Mach 30 at a target’s particular eyelash.  Following that up is grenade launchers, firing standard grenades at a target, using the same principals as a gravity gun, just with slower projectiles.  Then, you have many varieties of missiles, from “brilliant” missiles to hypersmart missiles that are probably smarter than the pony firing them.

Following that up is grav artillery, which takes the gravity gun principal and fires volleys of shells, volleys of hypersmart missiles, and small tactical nuclear devices.  Bigger fire support can be launched from orbit in the form of kinetic energy weapons of varying sizes (from “kill that guy on the street corner” to “take out a city” yields).  If you really don’t like a planetary target and have a battleship handy, hitting it with a stellar converter will get everyone’s attention.