RMXP or RM2k3, it is possible to do anything. RM2K3 only limits it to 700 common events or so, but RMXP uses scripts, and text doesn't take up much space, so it has unlimited options. A FFTA Battle system was already made by a scriptor known as Squall, but it was encrypted, so I can't share the script with you. Sword Of Mana? That can be done without scripting, just events and common events. Just make sure you never use the random battle encounter feature, or you'll have Legend of Zelda one moment and Final Fantasy the next.

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