the drop for the stones needed to upgrade towers during a mission is absolutely ludicrous, especially when it takes 100 of them. Plus, there really isn't much detail by way of upgrades (both in game and at the menu screen)
ehm.... there seems to be a little bit of non intuitive problem in the tree build UI, we will also try to fix that. actually you just need 1 seed to upgrade the tree to another form, the 100 is actually the number of fruits you need. so you need 1 seed and 100 fuits to change type of the tree. hope that helps :)
Thank you for playing~
 "Swords and Souls"){kind=icon}
 "the Utans -Defender of Mavas-"){kind=icon}
There is one! I'm working on it :)