G.W.I.: Combat Ability
I Battle Apprentice (B.A.)
II Battle Discipline (B.D.)
III Battle Adept (B.Ad.)
In at the first three ranks, it is expected to know a certain amount to combat spells of different classification in terms of strength. The higher the rank, the more proficient you are and more spells you know. The term 'strength' is very vague at this point, as it mostly depends on how you use your spells. The wizard should know the basic natural laws, physics, biology, chemistry.
IV Battle Master (B.M.) - required to cast partially chantless
V Battle Mage (B.Ma.) - All combat spells chantless
There is also a requirement for different kinds of spells mastered and the ability of a wizard is also a big part of deciding the rank. A wizard of this rank should have a deep knowledge in a single category, e.g. Heat, Laws of Motion, Hormones, ...
VI Auror (A) - Good combat power. Able to destoy a large manor in seconds
VII Hit Wizard (H.W.)
A Hit Wizard has started building a real, own combat style, own spells and partially wandless, integrating certain elements and deep understanding.
Note: A Hit Wizard should be able to destroy a village
VIII Elite Hit Wizard (E.H.W.) – Own combat style, own spells, mostly wandless
Note: An Elite Hit Wizard should be able to destroy a town with a bit of effort.
IX War Wizard (W.W.) - Fullfil special requirement
A War Wizard can cast spells whose requirements would be too much for any other wizard and is supposed to be able to apply understanding of the world (Universal Laws, Physics, Chemistry, Biology) seemlessly
AT this level, they were only separated by talent, understanding and imagination. They could literally bend reality.
Spells: They do not need special incantations anymore. They could use their special runes and layer hundreds of intents and thousands of hours of learning, understanding and enlightenment in one sentence or even word by saying it. But only a High War Wizard would be able to do it in one word.
Note: Able to inflict a whole city with one spell.
Currently known War Wizards: !STATUS NOT KNOWN! Albus Dumbledore (Br.), Red Assassin (Jp.), Steven Star (U.S.), Master Yu (Ch.), !DIED RECENTLY! Louise Delacour (Fr.), Sergei Dolohov (Ru.)
X High War Wizard (H.W.W.) -Current combat prowess not known.
Formerly: Albus Dumbledore, Gellert Grindelwald, Voldemort
XI Grand Wizard (G.W.) - Strength not known
Formerly: Probably Merlin, Helga Hufflepuff, Herpo the Foul, Solomon
Note: Nothing is known on how to rise above the strength of E.H.W., rumors hint to the involvement of runes.
Important note: Rank I – VII do not define strength but are decided by the skills a wizard possesses. But in most cases, a wizard would be able to back his 'combat magic rank' with real combat skill. A B.A. could still be able to wipe the floor with a B.Ma. if the gap in experience is big enough or it the B.A. fully mastered a spell.
The difference between reality and actual skill can be large!