HP will eventually out scale damage. So after awhile the best build will surprisingly be Hp + el-aura (+ universal aura). This is even better than HP+Nova.
hp + Nova is much better than normal damage. At least on high waves. This is actually all you need in the end.You can basically Just ignore everything except for hp Nova, rel resistance and interests (+special resources), white 1000%. Offense is not needed at all.
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