Here are some helpful tips for people starting out on this game. I am currently in the mid to late stage of the game and if I had known these earlier it would have been much easier!
1. Don’t buy random generals - Most of them are crap and a waste of medals. In early stages buy trainer generals to improve later generals. Mid level trainers are good for this as they have enough combat stars to still be useful for a while.
2. Save medals whenever you can - Don’t spend medals upgrading generals, use a grinding conquest save instead. Don’t buy items until you have a 5 star business general (20% savings on buying and selling, I use an upgraded Isabella). Don’t buy bad generals. Use your emblems for a tier 2 general instead of medals - wait until you have 4 and use them to buy one of the 900 medal generals (tier 2 generals can be bought for either medals or emblems).
3. Use the campaign stars sparingly to upgrade units - This is in the campaign menus and lets you unlock and upgrade units to use in the campaign. Upgrades and unlocks don’t roll over to other campaigns and you can’t un-upgrade to get the stars back. The important thing is that early on unlocks and upgrades are less needed, especially the upgrades, as you don’t need to use all the units so save them for later. I normally try to unlock everything except the forts and only upgrade the second to last infantry units (generals guard I think) as they are normally what I build.
4. Make a plan on what generals you want to buy and in relation to whether you want to pay for extra slots or not - My advice is to pay the $2 for the two slots, it helps massively (thats all I have spent on the game) and you’ll want them by the end. Also bear in mind that you have to keep one slot open for temporary trainer generals to improve the final generals.
5. Trainer generals are very useful - You find them mainly in tier 1 and some are cheaper than others (but are all as good as each other for upgrading). You regroup them into the general you want to improve.
6. Try to ace the campaigns as much as possible before finishing - This way you will definitely get the emblem (btw one campaign doesn’t reward you with them). You don’t need to 5 star all of them just make sure you averagely have 3-4.
7. Start grinding for medals/experience early - Its very boring so early on you can break it up with the odd normal mission. It speeds up the academy refresh button, something that is important to find the correct generals which can take a while to find. Medals are so important to improving your line up.