A group of misfit Chimera are transported to Equestria after the Battle of London. What do? Attack the royalty, that's what. To be honest, she started it.
Ortalians are the perfect soldiers, but do not hesitate to bolster their ranks with a wide array of mechanized units. Executioner-class mech is but one they employ to annihilate Empire's enemies. Then Discord happens and steals a mech.