Advice on leveling: Knight - Either go left for the ability "crushing blow" which is great, but his attack will suffer, or go around the right hand side where all the good attack upgrades are, but his "crushing blow" will be weak. Rogue - Go left, then up for "paralyze." She'll get her best attack upgrades along the way. Barbarian - go down one, then all the way right. Buy up the entire right hand side. "Fright" is just that ridiculous and the big attack bonuses are over there. Hunter - "Rain of Arrows" is very good, so buy left and max it out. All the best attack bonuses are along the way. Cleric - "Treatment" is amazing; "Healing" can be useful sometimes. I would get the two "treatments" left of start and then work my way to the upper right for the +3 attack square, snag "healing" along the way, and then get the third "treatment."
Mana equilibrium seems to effect chest odds. For instance, if you volley with your hunter to clear a fight so she is 35 mana behind everybody else, then that color is probably critically under represented during the chest puzzle. I've had chests where I needed to clear 5 out of 5 blocks on opposite ends of the field. When I started maintaining a balanced mana approach, this issue stopped happening.
And so the boss of the game was healed to full after 2 rounds. That's right, it healed 500000 hp or so in 2 rounds. I pummel it for 20 minutes and it cancels that in 2 rounds. I understand killing its wingmen stops the healing and I probably got unlucky. Yet I'd still rather stab my face with hot pokers than continue. To all potential RPG builders out there: Bosses that heal are not fun. Balance them so that they don't need healing. That's how close I was to the second hard badge, so 3/5.
For "gladiator" path, in addition to your main tree, grab the passives from the assassin's tree except the backstab one and work on getting Malicious Intent in the arcane tree. I recommend blinkstep. You will crit often and things will bleed to death. Don't add too much movement speed (warder tree) because kiting basically makes you invincible due to enemy attack delay. You want the monsters to catch up once you blink away.
Set out with 2 beasts, one front rank hitter Ghost, Fairy, Ghost. I used Triceratops, Elephant, and Tyro. Go left from the start get those treasures, then go back and go right, then up and over. Use Magic to revive dead animals at first. Once you have enough bonuses, you'll be using Drain a lot. Once you get the extra action item, you'll be using Power++ a lot. In the last level, your fairy will become an engine of destruction backed up by the ghosts and tanked by the beasts.
So, I have 4 maps left to complete. I have never hired a hero on a map, I have 1200 gold and I'm level 4 out of 80. Gold/Exp should be multiplied by 10.
First of all, great graphics. Definitely quality graphics. RPG? Seems like turn based battles with overly huge numbers. I want to explore and interact. Grinding through battles is the least appealing part of RPGs for me. Also, re-examine your cost to damage ratios. Air Strike is a very efficient damage dealer compared to, say, Catastrophe (which won't ever be used if it continues to kills the caster.)