I’ve been playing Cookie Run: Kingdom for a long time now and own solid teams. PvP, I’m constantly in Arena Master ranks. PvE, I’ve completed all the available story mode stages at the time of writing.
With a gacha game like this, you obviously can’t guarantee what your team will look like since it's all up to RNG. However, you can plan & take decisions which will almost guarantee you a strong team in the future.
To simplify, I will split this guide into 2 sections — Team building and Kingdom building.
1. Get as many initial crystals as you can
First thing you should be doing is rack as many crystals as possible when you start the game so you can spend those crystals in the banner to get as many cookies as possible.
There are multiple ways to get crystals in the beginning — completing story modes, mail rewards from devs, achievements etc
You can also get free crystals by redeeming coupon codes. Devsisters regularly provide new codes which give you amazing rewards for free!! A simple google search should give you the up to date codes. You can then redeem them at https://game.devplay.com/coupon/ck/en
The reason for getting crystals is — you are trying to get as many epics (or higher rarity) cookies as possible so you can have a strong starting team to carry you forward.
Note: Not all the epics are good! But for now, any epic would do because higher rarity cookies means higher stats.
If you’re lucky enough to get one of the top tier cookies, then congrats!
2. Go through the latest tier list
Once you spent all your crystals on cookies, next thing is to get an idea of where you’re cookies lie in the latest tier list. It's good to know which cookies are worth investing and which are not. At the time of writing, few of the must have cookies for any team are — Hollyberry, Pure Vanilla, Sea Fairy.