you don't need a secondary school, period. doesn't matter what school you are~ they are useless.
that said, if you are concerned about death's lack of an attack-all spell and are below level 48, go with myth as your second. you will have 2 attack-all spells to use, and your spirit blades will be good for both.
They start with Strong and end with Colossus. They continue on the Floating land and then Colossus is in Zafaria's Drum Jungle.
You don't have to take any of the other spells offered just the fists ones. They cost 5 training points to collect them as you have to take them in order to get Colossus.
You add the sun card to any of your school given damage spells and it raises the damage by the amount of the sun spell. The ones offered in Aztecia are also helpful and I have collected them also.
I find with any school it's best to try to be very careful with out of school spells. Wait to get them till you are really sure you need them. Training points can go fast and the quests to get them get harder as you advance in the game.
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