thor doesn't target empty cells, his auto-ability (read his description in the select opponent screen) allows him to smite all cells when he casts a spell, empty or not
zoidaki: there is a Q & A in the forum posts: only 5* and 6* can evolve for now
franjo: try refreshing the page, this happens to me sometimes as well but refresh and it should add the missing stuff
@OhJoy and fearden: evolving requires you to have two of the same 5* or 6* cards (lower levels will be in next updates). Make sure none of the two are currently equipped to one of your champions. You can evolve your cards no matter what level they are, the evolved card will receive the exp from both previous cards. If you need more help, there is an evolve Q and A in the forum posts.
@bekh you can only evolve 6 star cards at the moment, you'll need to wait until next updates, then you can evolve 5, 4, 3 and 2 star cards, I don't know when the updates will be though
@Erero: ask your friend to build a weak deck so you can beat him, after you've beaten the chapter he can change it back or use another deck so he can still play as well, hope this helps
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