Playing Paladin's Quest, and got the Adult cl to drop on the second attempt. It's actually a really good piece of armor, despite it having only 3 defense.
I think I really like the way Paladin's Quest handles its two rare drop only items. Thing is, rather than making the drop rates really low, the developers instead put the drop onto a special sort of enemy, one that isn't a normal enemy that would appear normally in a random encounter, but isn't a boss either. (In the case of the Adult cl, it's dropped by a townsperson who attacks when you leave a certain building at a certain point in the game, and that fight can be repeated if you leave town and return as long as you don't progress the plot; in the case of the Gomutai (two-handed sword with high attack), it's dropped by a special enemy that only appears if enough ghosts run away and follow you in one specific dungeon.)
So, while the battle you need to fight isn't typical, once you do get into the fight and win (the Adult cl fight is trivial, while the Gomutai one should be treated as a minor boss fight), you have a decent chance of getting the drop.
I much prefer this to the more common approach of having drops come from random enemies at very low probability, or even worse, having the drop be a random drop from a non-repeatable boss fight. (My only real complaint is that the Adult cl is permanently missable, but at least the game has an accessible debug menu if you *really* want it.)