yoshino: Elminage Gothic.
My average level 16 adventurers, explored the church's under dungeon and finally meet the boss of the dungeon.
He was too strong, The 3 adventurers in the front position were killed just 1 turn, and he regenerated by 100HP. In the next turn, the party was annihilated of course.
I could not find how beat this too strong boss.
Anyways, In the 2nd try, my samurai had a spear which had been enhanced by alchemy to instant kill by 7%. And his behead attack succeeded.The strong boss killed without any damage to the party. :D
This game is a lot of fun.
You're also at the point where you can power level rather easily. Hint: There's a certain enemy in the lower levels of the dungeon that can call for help, but is otherwise not that dangerous and can't wake up. Also, characters who run from battle don't get a share of the experience, allowing you to give all the XP from said fight to one character if you so desire.
Also, it is not safe to assume that bosses are immune to status effects, as you found out.
The in-game bestiary definitely comes in handy. If there's an enemy that is a pain to kill or is quite dangerous, check its bestiary entry; that might give you insight as to that particular enemy's weakness. Even the most dangerous randomly encountered enemy has its status vulnerabilities (though that's not really the issue with that particular enemy, anyway).
Anyway, in Mega Man: The Wily Wars, I beat Mega Man 1; now on to Mega Man 2. I believe the final boss of MM1 takes more damage from the weapon I was using than in the original; sort of makes up for Cut Man not being feasibly killable first.