It took me over 1300 tries to get her (3 days of regular troll battles and before I went to bed I had to spend exactly 60!!!! refills) - after a certain point I pretty much only continued to see how far I can push it until I get her - not sure what they wanted to achieve with the legendary days, but this should discourage anyone from actally spending money on the game - the kobans I used translated to nearly 80€