Yes there are a lot better ones. I will need to look it up after work myself so i can say for sure but if i remember correctly there a more with bigger boosts. I think Undine's Cloak is the best one by far and slime drenched robe was pretty decent as well i think. There are also a few items under "Other" that also can affect heat and/or cold if you got any. I think there are also fewer heat resisting clothes than cold ones. It is meant to being able to be done without relying on insanely high max health but it could be that there are a few to less clothes to ensure players find enough. I will add a few more to the armor shop in town after its upgraded so it is easy to access.
That also is a good point, i should give some rings a cold/heat resistance boost as well. I will look into that.
It is absolutely possible to get heat and/or cold up to around 700 with the right gear. So you probaly just were unlucky and found none of them yet.
No each key piece is in on of the plains, except the eastern one, that is in the frozen tundra. The new owl upgrade makes finding that one a lot easier if that is the one you are missing but it can be found without it as well.
Oh i see, the gacha to get cards is located in the casino. If you dont feel like gambling the next update will introduce a way to buy them as well for money.
Yes it is usable and also related to the broken key if you want some hint!
Glad to hear that^^
No worries it is still a work in progress after all so some things might still not be perfectly balanced or have a few too less hints. It also helps me realize which part could use some more directional hints for the players : )