If you keep crashing your ship into the bosses they wont attack you and you can keep healing yourself with b. It gets even easier once you get darkness energy charge because you'll never run out of mana.
The Sky Dragon works well on epic goblin madness but he has trouble advancing. Lord of Fire with chain invulnerability can continue advancing while killing goblins making him awesome for this level. I try to save invulnerability for just when he hits the black goblins and I keep it up until I run out of mana. Usually he'll take about 1/4 of the castles hp.
I recently made the 15 brilliant ratings. Here are a few tips...
The crypt towers were easily my favorite, towards the end you don't need much else. Get the fear upg. and freeze upg. and its pretty much GG.
When facing a ninja boss make sure the crypt towers hit him first. If you're lucky he'll be frozen before he has a chance to go invisible.
Get the skills to turn 50 mana into 100 gold. Although its not necessary, it can be helpful when you're sitting around with huge mana reserves.
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