start at the edges, and eliminate every false possibility by rotating the pieces so that they make sense (i.e. straight pieces cannot point out of the square).
interesting that the damage multiplier doesn't also affect the size of the crater created in the planet. it'd be kinda cool to have a missile fly around space for a bit, then completely destroy one of the worlds.
level 12 seems uncommonly hard. it seems as though it would be easier without the mining skill which gives you one extra gem, since that way enemies would have to travel farther into the caves to reach them, especially with the ridiculous amount of ninjas at the end. it seems like no matter how much mana i have there really isn't much chance of stopping them before they reach the first one.
i've been wondering since the first game what the point of the return portal skill is. if it's only to still keep an "excellent" rating on a particular level then it seems very redundant. it seems like it would be more useful in giving you a "brilliant" rating on a level if at the end all your gems are in the cave.
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