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Advance Wars has used abbreviations for its units since AW 1 on the GBA. They are generally very easy to figure out and exist only to save space. In addition gamers and message board posters have been using acronyms for commonly used terms. They are listed below in the form given and sorted alphabetically.

A-Air

Anti-Air

AoE

Area of Effect, attacks that hit all in a given area.

Artlry

Artillery

CO

Commanding Officer. Also, CO Power meaning the first tier special ability.

dmg

Damage

FoW

Fog of War

HP

Hit Points (less common, Health Points).

HQ

Headquarters

Inftry

Infantry

JPN

Japan or Japanese, using JAP is considered offensive.

M Gun

Machine Gun

OHKO

One Hit Knock Out, or Instant Kill.

SCO

Super Commanding Officer. Usually in the form of SCO Power, meaning the second tier special ability.

TBS

Turn Based Strategy (not Turner Broadcasting Station)

Torps

Torpedoes