Challenge 8: my white vs his purple, with life boosters on both sides and the enemy recycling my troops. By the time I did 170 total damage to win, my health was up to 170. Good times.
You're not really intended to finish campaign mode, are you? Who wants to sit through hours and hours of killing the same little guys, even if it were possible without cheats?
The Grey Games levels are good. The Azurieq levels are poor: trial-and-error suicide is not a good design decision. The assorted levels are a mixed bag, with some very good puzzles.
Why are folks saying the challenges are bad referring to the badges? It is not about whether the badges are hard to get. It is just poor design. For example, if you start the challenge with 5 health and lose if you go insane, there are 11 cards that will cause you to instantly lose, and 2 that will make you lose no matter what at any point (both drive you insane). There is often no defense. At that point, you are playing the game of coin flip: will the computer randomly make you lose this turn? The impossible badge is not even difficult, just extremely tedious as your restart, lose on the first or second card, restart... It is like trying to assassinate President Madagascar, another poorly designed "you randomly lose and there is nothing you can do about it" game.
Commenters have a point on the luck-based challenges. There is not much to be done when you lose on the first card. Other times, it becomes trivial as the computer plays cards that are worthless or actively harmful to itself.
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