It's pretty late right now for us, but we'll be sure to add some guides in the description in the game later on! Thanks for telling us :D
Edit: It'd be helpful if you mention what you struggled with in the game, so we can add more helpful descriptions! Some general tips, some cards have gimmicks and stats that make them good counters to certain enemies, or make them synergise well with each other. Make sure to right click the cards to see what it does! The items ( at the bottom left) are quite helpful too, use speed ups to make your units attack faster, and slowdowns/pauses to debuff the enemies by dragging it over them. (small tip, BIG BEN is a very strong card early on, so try to save up for it and use some items to support it)