State of Economy: +10 (Flourishing), +7.5 (good to Okay), +5 (Mild), +2.5 (Poor), 0 (Non-existent or collapsing)
Many or major defenses and fortified places: Defender + 10
Technology: 0-9; with 0 being the worst, 3 being poor, 6 being normal and 9 being ahead of time.
Knowledge of landscape: +20 for in one's homeland, + 10 for warring in an adjacent nation, -1 for low knowledge of an non-adjacent lands which are on you continent, -10 for no knowledge of a distant realm that is not even on your continent and in polar regions (unless the attacker is also polar)-11.
Each nation fall into a power category, +1 for each category. If your a failed state 0. If you're a super power +5
Side with greater population: +3
Side with greater industry: +3
Urban warfare in big cities of over 5,000,000 people like London, Tokyo, New York, Shanghi and Berlin, Attacker-2, Defender+2
War Weariness: If you have been fighting for more than 3 turns in a row -5 each turn due to battle fatigue until you make peace for at least 2 turns.
If either side nation deploys over 500 Tanks (or main battle tanks after the Panzer III and alke were invented), 1,000 bombers, 10 attack submarines and/or 10 men-o-war, Ironclads, dreadnoughts, battleships or aircraft carriers (depends on historic time) in the war then they get +1 for land, sea and/or air. Remember to say how many you deploy or it will be guessed or ignored by a mod. Modern large war ships also take time to build.
Morale: -10 In face of larger army, -20 for completely surrounded, +5 for in face of a smaller army, +10 for surrounding enemy. If defeated last turn, then the looser from that battle is -5 to his opponent in this battle
Storming on to a coastline from the sea or on to an island, the attacker - 4 and defender + gains 5.
Storming in to a desert, high mountains, polar or jungle the, attacker - 3 and + defender gains 4.
Nuclear war gives the atomic user +10 and defender -10 for strategic arms, or +5 and -5 for tactical arms, or +2 and -2 for SDD/SDM sub-Hiroshima and 'suitcase' mini-bombs. Also add +1 to the attacker and -1 to the defender if the capital is hit. Also add +1 to the attacker and -1 to the defender x the number of nukes used in the attack as a grand total.
Chemical weapons give the attacker +2 and the defender -1.
Every nation militarily helping with their side= +2
Every nation offering supplies to their side= +1
Every vassal nation, guerrilla force or terrorist cell any way helping with their side= +1
Religious motives= +6.5 to the attacker and - 0.5 to the defender.
Political and moral motives= + 6 to the attacker.
Ethnic and cultural war motives = + 4 to the attacker.
Economic war motives = + 2 to the attacker.
Regional tactical Advantage: +5 defender/-3 attacker (for example crossing the Kalahari desert)
Armed expatiation in large extremism climates like Greenland, Niger, Nepal and Amazonia will also be very slow due to logistic and climate problems for any wood-be invader. In this case the defender gets an advantage of +5 and the attacker gets a disadvantage of -6
Victim nations' life or death = + 10 to the nation who is fearing being wiped from history, +5 if facing losing over 10% of it's territory.
Strength: # of troops divided by a factor of 20,000 (IE, 1,000,000 = 50 points)
Add the totals up and find the biggest total. The biggest wins.