Easy way to take out First Adventurer: get his attention, run back down to the cannons, stand in the lower left corner (where there are no cannons), and let him shout decidedly empty threats while his own defenses put large, fiery holes in him.
In addition to the other suggestions, I kinda hate the trend of unceremonious endings. I just wasted like ten hours killing everything that moved, and most of the things that didn't. Can I get some fireworks or something? Maybe a digital chest-bump?
You can get double hits out of your special attacks. Be at least a square away from an enemy, highlight the enemy, click a special attack, and right after your character completes the move, click the enemy again. Booyah.
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