
Originally Posted by
master130686
I support A casus belli system, but not the one from Europa Universalis (or any other Paradox game - least of all that of Crusader Kings 2).
A casus belli should indeed create a "reason for war", but the war should not be limited to the original casus belli. If a war is declared that is based on a casus belli, the "goals" of it must be reached to win the war. But if you're able to do way more than that, you should also be rewarded - as should you be punished if you don't reach those "primary goals".
The rewards and punishments may include payments, regions, troops (e.g. give/recruit an army of a certain strength or size or pay the upkeep of the opposing faction/s) and/or diplomatic actions (like forming or cancelling alliances, trade agreements...).
Payments, troop arrangements and diplomatic actions should be limited to either one-time "actions" or to a limited time period - like "give an army of a certain size and/or strength and pay the upkeep for X turns/years" or like "give/recruit a certain quantity, quality and/or type for the opposing faction/s within the next X turns/years".
How much and for how long should depend:
a) on the warscore (the difference of battles lost and won)
the score should depend on how many men fought alltogether, on each side AND in relation between the sides (both the relation of the numbers and the strengths of each side). Therefore a battle 200 vs 200 (strength 1:1) should get a higher score than a 300 vs 100 (strength 3:1), but the same as a 300 vs 100 (strength 1:1), but also way less than a 2000 vs 2000 (strength 1:1). And the kind of victory (decisive, pyrrhic, normal...) should be important.
and b) the difference in strength (economic, military...) between both sides (or at least/sometimes the faction who declared war and the one that war was declared on - allies not counting) BEFORE AND in relation to the difference AFTER the war.
The higher the difference AFTER and in relation to BEFORE the war, the longer the time and/or the higher the reward/punishment.
But you should ALWAYS be able to declare war on anyone. The main difference would be that negative war effects (like the territorial expansion malus - tem) would be smaller or none existend for the casus belli. If e.g. the casus belli includes a certain region, this whole region is tem-free. Everything beyond this is not. But if another faction has the same cb on this region, you still get the tem with this faction - maybe an even higher one. It's similar to then-to-be neighbouring factions.
So if you try to annex the hungarian crown as Poland (in a Medieval 3 setting), you get no tem with Sweden (you usually would get the usual tem for each region without the cb), but you'd get at least the usual tem with the Bycantine Empire (if not a higher - e.g. if the annexed regions include some that they have a cb for).
And you should be able to expand cb's. Like when you have cb's on several regions of an opposing faction (or alliance), you can add other cb-regions during the war, if the warscore is high enough.
What I like about Europa Universalis is that you can decide at the end of the war (if you win of course) which region/s you'd like to claim (with or without cb, though cb-regions are mandatory) - if you can afford them, according to the warscore. That is similar to the way you can demand additional regions in Rome to Napoleon But you don't automatically get the "conquered" regions AND demand others. You decide the regions you demand/claim at the end of the war.
This would mean (in an Empire setting):
If you declare war on Spain as France and "conquer" all european regions and some none-european, but you decide to demand (at least some of) their american regions, you get the demanded (implying that the warscore is high enough) regions, but Spain regains full control over their european ones.