Monks with double Swords.
Or Orlandu on a Red chocobo
Or.... ok.. there are millions of other cheap tricks, but I won't go into them all.
Blade Beam on Final Boss!
Monks with double swords??? How does that make any sense???
But yes, u are right that there are other cheap things ....like mediatating monsters you arent supposed to...but these are some basic ones that can be used early in the game