Very fun game, 5/5. A level editor would be an awesome feature in the future.
Press down to not stick to walls (It helps, but I also agree the walls should be less sticky).
Finally got the impossible badge as a bio... speed build in area 6+7 is helpful (corrosion, toxicant form, shadow blend, agile exposure and withdrawl hit for 30k) Mayor is I thought was the toughest fight in the game.
I found Crystallize to be one of the best abilities for a Bio. I am currently playing on Heroic, and if you put all your points into vitality, gear for max vitality, and also use crystallize (to stun powerful enemies, get healing breaks), Heroic mode is much easier.
I watched every second of it - and the ending was worth it. I highly recommend investing your time into this game because it takes a true champion to watch every moment.
How to get the Brick: 1)Click on Glider 2) Go to the last page 3) Click on blank space under the Whirlybird 512 4) You know have THE BRICK [+] so people can see!
Tip: On the Silveroak Outpost level, you are able to repair the little house in the upper left of the map for 100 gold. You then can create Sylvan elf warriors for 100 gold each (max 4). Also for the Iron challenge here, you are able to repair two of the elf training halls. Use the elf warriors like Barracks and group them to make it easier for Artillery/Ranger/Mage towers to kill the ongoing flow of enemies.