Following armies do not exist but they are presented here to provide gamers new armies to fight with or against.
Harjoitusvahvuus D is Finnish Defence Forces exercise enemy published in 1956. This enemy (D) differs from B (USSR) and C (USA) in that it is imaginary enemy organization that is used to depict force intended to fight primarily a nuclear war. It is rather sketchy but could be interesting one-off to put against other Korean war era units.
Harjoitusvahvuus A2 Keltainen is a Finnish Defense Forces exercise enemy published in 1980. It describes a "Soviet American" military that combines equipment, TOE and tactics from both US and Soviet armies. Its equipment and organization is fairly typical to 1970's and thus it would offer interesting opponent to players interested in playing that era.
OPFOR is US Army's current exercise enemy. It is quite flexible opponent offering great freedom in organization and equipment allowing tailoring it to meet almost any level. OPFOR is based on Soviet organizations. This organization allows fielding almost any and every model to build up a force that could be pitted against any existing force, if care is taken in ensuring rough balance.
GENFORCE (Canada) is Canada's Defence Forces current exercise enemy based on Soviet organizations. Rather interesting campaign could be built when it is pitted against X Allied Corps. This force is used in exercises against GENFORCE. This force is quite well equipped and it is roughly equal to high end of OPFOR that offers challenging enemy those interesting modern equipment.
GENFORCE (UK) is British Forces current exercise enemy (actually one of them as ROWEN is the another). It is heavily equipped military following Soviet organization and tactics. This is very hard enemy to fight against and should not be tackled unless one is looking for quite challenging enemy.
Victor Suvorov's Soviet Army is built on ideas represented by
a Soviet defector "Victor Suvorov" in his book (some would say novel) "Inside
the Soviet Army" in 1982. The book represents Soviet TOE that varied greatly
from then existing real Soviet units but with help of Suvorov's book and
OPFOR organizational charts rather interesting and heavily armed Soviet
TOE can be presented. This would be ideal force for players interested
in fielding a large and heavy force.