This is a cross post from here: http://guilelessmonk.tumblr.com/
Boss battles should be the culmination of what you learned throughout the stage. That seems like a really obvious thing but it is surprising how often that is forgotten (I’m looking at you Deus Ex:HR), or what its real implications are. A game series that tends to do this right is Mega Man. Did you spend the level sliding around on ice? Then what do you want to bet the boss will cause you to slide around on ice?
But while it is all well and good for the boss and the stage to share the same mechanic, it is also important to note that the game should be similarly constant in how it teaches you play the game. To explain what I mean, I’m going to talk about FF6 for a second.
When you go through a dungeon and fight the enemies you are not really concerned about the enemies being strong enough to kill your party if you fight it out, what you are worried about is that you will use too much mana or items while beating them and so will not have enough to take out the following waves. In this sense, the game is an endurance contest, and it is best to fill your party with people who can do good damage for 0 mana and not people who do shit tons of damage for 5 mana. But boss battles are different, you have just healed and saved, you know you will be able to save after the boss again and so you aren’t worried about conserving your mana. In boss battles you are generally concerned about dealing as much damage as fast as possible (though you still want to not use up certain items you can’t restock on) and so you would want to prioritize people who do shit tons of damage for your party line up instead of people who can always do some.
In Final Fantasy: The 4 Heroes of Light they use a different mana system where you have a max of 5 mana and gain 1 every turn. I like the idea behind this but the problem is that it creates strange optimal play. Because you gain mana in battle but not outside of it, your goal in a battle isn’t to kill the enemy but to cripple them and then heal your party and max out your mana again before you finish off the enemy. I really like how it identified the problem but I’m confused why they didn’t take it the single step further and just make it so after the fight ends you heal up.
Penny Arcade Ep 3 does this (and resets your items and mana to 0 at the end of each battle) and is better for it. Resetting health and mana after every fight allows you to make each fight interesting and dangerous in its own right and not just as part of a larger endurance match. It also creates consistency in how you fight, each fight you go all out and so when you fight a boss it is the same thing you were doing before but harder.
Consistency between stages and bosses is important because otherwise it is like you spend an hour teaching someone math and then quiz them on history.