Save your elixer no matter what you come by, until you need to use it, and do not Buy that instant kill, just Shortens the lentght of your progress. once you use the elixer, all you need is the Armor shop to replenish HP. (With new armor ofc, and more hitpoints.)
I read on Previous comments abotu there being a tournament, And if you win you get armor, I dont know where there is the tournement and if they are teh yellow Sword X circles, then how many rounds do you Play?
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