HARD BADGE GUIDE: Every level can be beaten using solely Bunny Archers (2nd unit unlocked). Use money to upgrade, skill points should be spent on increasing food production, max food limit and mana production, and increased burst skill in that order. During each level, wait until you can train a group of archers (use mana to food production to speed up the process if required) and train continuously. They have a longer range than most units and are devastating in large numbers. To boost attack power, have archers positioned within Paladog's range.
Done right, each level should only take a couple of minutes; enemies won't be able to leave their base
Speaking of builds, another awesome one is to have a pure prowess build. The idea with this build is to deal tons of damage quickly, and end fights before the enemies can deal major damage.
Invest in Seeing Red to increase power, and in Shockwave for crowd control. Also get Meteor Shower for bosses. Preferably, dual-wield fast weapons, and equip armour with high energy regen. Goes without saying, put all level ups on prowess.
As for tactics, use Seeing Red before entering battle, engage a small group of enemies and use Shockwave them. Take out any stragglers. Rinse and repeat. If you draw too many, or get ambushed, Meteor Shower will make short work of them. Feel free to make your own changes and tailor to your playstyle.
Good luck!
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