While it may be fun for a boss to meticulously lay out a plan for dispatching whatever would-be hero happens to be trolloping their way, the greatest of props are delivered to those that just prefer to duke it out and see whose energy runs out first. Still, while it seems a bit savage, there’s strategy woven even in these bare threads.
Por exemplo, the boss is, nine times out of ten, at an advantage with this method. If the minions and traps peppered throughout his domain have done their respective jobs, then the hero(es) should be a bit worse for wear than their adversary; likely waiting patiently with goblet (or a jug of Midnight Train, depending on their evil social status) in hand.
It’s also just plain gnarly, right? The hero dashes in expecting some drawn out battle and suddenly the two are just lashing and stabbing back and forth until one falls. These are probably the most “realistic” boss fights.
The first games that should come to mind in these cases are the above pictured Castlevania and Ninja Gaiden series, though the former stopped using this technique for the most part once it started leaning more toward exploration, and the latter since it stopped being 2D.
These are what got me on this mental kick, specifically the badass NG2&3 runs by Jim Hanson.
subhumanzoids 
wow. i was just checking these out earlier today, much before i read this post. joe….this can only mean one thing….my wang is destined for your anus.
Obviously!
Death in Castlevania was always such an asshole. But alternatively, if you want to kill him easily, it also involves throwing strategy out the window and bombarding him with holy water. Here’s a video I put together – http://www.youtube.com/watch?v=K1tnFGcYzew