Apart from the chance of headgear, I don't really see any point from the card battles and raids. You can get crystals, which are just going to be used for more card battles, and exp for the heroes which we really don't need for anything other than card battles.
Also, with 14 purple heroes level 5 is a challenge. There aren't exactly a large amount of people with that amount, and most of top players probably won't be able to beat past level 2 or 3. Even with 8 purples, which is the maximum for the large majority of players, level 3 is a challenge. And this is taking into consideration they find an ideal build for themselves.
While I think that this is a very good idea, I find that too much of it is left to chance. People are not going to have that much gold in the real game, which means they will take whatever hero they get of the purple tier. Since most of the people already have a build of 5 heroes attacking, 2 build, and 1 tech it would be problematic since they could be stuck with classes they would rather not use. Also, since the 4 classes are different for the 4 races, a person could possibly have all of the same class of hero, and would have no strategy whatsoever. Having a variety of unique classes is good, but leaving which ones you receive to chance is not.
Did anyone else see a clear ghost ship? O.o
Oh yeah and I met up with a ship getting attacked that had a yellow hp bar. Do I get it as a ally if I kill all the pirates attacking it?
 "Time World Test"){kind=icon}
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I'm fixing it!