Rule Changes
Expansion: You can now expand into any provinces bordering a sea your territories touches as well as any provinces bordering any seas which borders that sea. Heres a handy map if you own Rome (dark green) you can expand into any highlighted territory. Same rule applies for validity of amphibious assaults.
You cannot move your armies into allied territories anymore. I've thought about allowing it but it's just too confusing. Allied armies, however, can still aid in defence if they are stationed in a province neighbouring to that getting attacked (see below)
Each province will now only have one value assigned to them which is the Strength value.
Forts have been abolished; existing forts will be merged with Province Strength value. Province Strength provides Income as before (1 point of Strength = +1 Income Per Turn), but will also provide a defensive bonus equal to 5% per Level. The cost to upgrade is the same as before, ie if you have a Level 5 province you need 5 Gold to upgrade to Level 6. The maximum level is still 20.
UPGRADE IS LIMITED TO TWO LEVELS PER TURN.
Units (armies and navies) are now more important with the absence of forts.
You probably will not be able to protect all your provinces with an army, so smart army and navy placement is going to be more important.
Armies will now cost income to build. The cost of an army to build is equal to the number of provinces you have
if you have 20 provinces, you need 20 gold to build an army or navy. Armies cost
upkeep equal to n^2, where n is the number of armies, which is automatically deducted from your income. The cost and upkeep is the same for navies.
Traits have been changed:
Amphibious: Army suffers no penalty in amphibious assaults.
Desert Fox: +25% bonus fighting in deserts and plains.
Garrison: +50% defensive bonus due to Province Strength.
Logistical: Army can move/attack two provinces per turn instead of one.
Mountaineer: +25% bonus in hills and mountains
Ranger: +25% bonus in forests and cold forests.
Siege: Half enemy defensive bonus due to Province Strength.
Training: RNG rolls will not add less than 10%
Battles
Attacker: An army that is conducting an attack move cannot defend its province if that province is being attacked in the same turn. Also, you have to explicitly specify which armies you want to be involved in an attack; neighboring armies will no longer automatically join the attack.
Defender: If you are attacked, any free armies (as in, not moving or not being attacked themselves) in
adjacent provinces or bordering the same sea (and not blocked by an enemy navy) will automatically assist the army in the province being attacked.
If the strength of the victorious force is more than twice the defeated force, the defeated armies will be disbanded.
You dont lose any army/navy quality from either building or losing armies/navies anymore.
Finally, when giving your orders please state how much you want to spend on something. Please see here and here for examples. It really helps. Thank you.