A possible stoyline for the third:
Neighboring countries have recently been taken over by "Dramatic Bad guy name". Start out defending your kingdom, and after youv rid the enimies their, head to neighbor kingdoms and assist them,the final mission until that kingdom is finish should be a boss battle, like a dragon orgiant or aartillery, etc. once a neighboring kingdom is relieved, they should give you a reward, wether its a trrop or artillery. You shoud also be able to do missions for them once you have relieved them. Once you help out all the kingdoms, head to the enemies country and take over their forts. then you head over to their castle, fight fight, then have an epic battle at the end.
Once your finished with the storyline, you should have an aftermath, having updated special missions and helping your kingdom. Very RPG like idea.
Sorry for the long comment and suggestion.
I would love a third Kings League. This was amazing. Here could be some possible ideas:
Thieves can be found easier.
More Recruitment Areas.
More classes.
Add artillery! Like cannons and catapults!
Some missions could at a different perspective, like a defense styled mission where you have archers defend a castle from infinite invaders for a time limit.
You should have a starter class, where you choose from 3 classes (idea similar to Pokemon)
Make cutscenes!
Boss battles!
Add weather effects! like thunderstorms lower/raise ability or hurricanes shut down routes to towns.
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