Each island has a ranking and maybe it's just me, but I can't quite figure out what it means. It could be referring to the player character level or the sprite's character level (both can be leveled independently), but something seems off as both can be well above the island's rating and we can still get our butts handed to us. But as I said, I may just be playing it wrong.
That being said, you do have to manage your forces once they are off the boat. It may be tempting to try to hold on to your special powers until you get closer to the final onslaught but you can also find yourself out of that particular unit and thus out of special attacks. Also, timing your initial special attacks is important if you want to have a chance to use it again at the end of the level. The attacks cool down at different rates and vary in effect. But if your little dudes are killed off before you reach the end of the clash, you basically saved a special attack for nothing.
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