8 characters, each of their abilities that are their own, and very complex strategies mixture between 4 types (basically to put it simply: earth, water, fire, air, even if it says otherwise: Mercury, Venus , Mars, Jupiter) are the equivalent of the 4 towers used in Golden Sun GBA.
One tip though: first emulator to play on games 1 and 2 of GBA to understand the characters because personally I've played one but never finished, so we know the characters, but the villains become kind or another, I did not know .
One advantage that I do not really enjoy but which remains: it has 8 heroes but only 4 are playable in combat. at the end of combat, 8 receive the XP too, so we rarely exchange compo personal and I almost kept the first 4 all along, which is a shame.