Fighter Gold is mostly just a grind until you get a spawn that you can beat. It's basically a test to make sure you know how to use the glyphs it throws at you.
Make sure to prep the Transmutation Scroll so that you can get quick access to one of the items in the corners. I'd recommend the Sword, since you can always use ENDISWAL or PISORF later to get the others.
Try to kill the highest level monster visible whenever you can. Once you get into the later levels, consider using the Slayer Wand on it to conserve resources. You'll definitely need a mid-fight level up to beat the boss.
Finally, LEMISI is a trap. It's decent early enough, though probably not more so than 100 CP, but using it against the boss is suicide. He has Fast Regen