cool
I finally beat the entire game and all the challenges, to beat I thought the hardest challenge was challenge 13. It was pretty enjoyable and a good time killer, It took me a while to figure out how to use my cards effectively but the game was really easy afterwards.
Hint for future players: I figured out how to beat challenge 20 on the second try, he cant be hurt by magic but if you use one of the attacks that ignore elder sign and invulnerable(such as raid or shotgun, or tommy gun), then you can kill him.
Also, for challenge 16, you dont lose when you go insane(even though it says so).
the strategy that ive written below is pretty much common sense, but would probably be helpful to new players
strategy: was basically to use any taint or monster cards immediately(unless the opponents starting health is above 40) followed by cards that add to your elder sign, then cards that boosts the arcane sign and lastly, use the cards that purely deal damage. If the opponent has a lot of health you might want to stall for boosting your arcane sign a bit and then unleashing all the attacks that receive damage boosts from arcane(lets call them arcane attacks). As soon as you boost your arcane up you want to use all your arcane attacks before the opponent dispels your arcane and before he builds up elder sign too much. Finally, use your attacks that ignore the elder sign and invulnerability last. Try to remove the other monster before attacking so that you dont receive damage back, if you elder sign is equal or greater to the amount of attack that the other monster has then you dont need to worry as much about it.
dont worry too much about going insane if the other guy is on low health. when you go insane its useful to discard your extra creature cards, they're not as useful as you think they are since you can only have one out at a time