aperson, if you're talking about the first Epic Boss, the key is to save up a few thousand mana before you get to him. When he gets to the end of the map you'll lose a ton of mana, but he'll go back to the beginning of the map and you can shoot at him some more. Click on the boss and a screen will tell you the cost for "banishing" him when he reaches the castle.
Emojk, you can win any epic level with any combination of gems. Just save up a bunch of mana for the end. When the Epic Boss reaches the end, you'll lose some mana but then he'll run through the course again.
Dual Mastery increases the effectiveness of Dual Gems, the gems with two colors. If you click on a gem, there is a list of the bonuses that duals get. That increases as you put points into dual mastery.
With the epic bosses, remember that if you save up a little mana, you can survive them getting to the finish. Click on them to see how much mana they eat up every time they make it to the end.
I jumped on the boss and he turned red. Then I fell on him again and I turned red. Now the screen is black except for "Final Boss" and "Lives 6". So the game is frozen and I can't get the badge.
I hate, hate, hate losing stuff when I die. It's not like I can go find weaker monsters and level up, if something strong enough to kill me before, taking my weapon away completely screws me.
Control is kinda clunky. Using the arow keys to move the camera puts your hand far away from other useful keys. I often click on the screen and it deselects my unit instead of moving it. I don't like that upgrades don't affect already built units and there's no way to retrofit or sell them. Using or to make the most powerful unit fire is painful in survival mode.
Sometimes submitting my score doesn't work. The little twirling arrow in the corner doesn't appear and I don't get a window. Since I just scored my highest population ever, this is a little bit of a let down.
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