I'm pretty sure that every time I hear that a game has a boss rush mode, I become much more excited than I should be. Granted, learning that any additional mode is included with a game should raise the excitement bar if even by a small amount, but a boss rush is nothing really to be praised. For those of you who find no greater pleasure than to embrace the boss rush in shmups, I'd love to hear what it is that makes it better than any other mode (well, at least arcade and score attack). But first read through my rambles for some good dirt to fling back.
The basic idea of a boss rush is that you face all of the bosses in a game, in order, from start to finish, with limited to no breaks for refilling health, upgrades, lives, sanity, etc. At a glance, it's a true test of one's ability to face against the roughest sections of each level - the boss itself.
The term itself is either an oxymoron or a redundancy. A boss rush should be just that - a rush. What constitutes something as a rush? That would be the contrast of a calmer state of being elsewhere in a level / game, in this case that would be each level's travels leading up to each boss. Take all of that build-up away and you're left with just intense action with hardly any contrast (not exactly a complaint... yet). An analogy I always enjoyed is that there can't be a superhero in this world without a super villain to validate the other's existence. Contrast. Now, looking at the term from the other side, the boss is the rush. It's like asking someone to pass the red ketchup (please disregard and burn all memories you have of the purple and green ketchup from the 90s, for the sake of both keeping my point valid and letting you sleep at night).
Yes, there are a bunch of other games out there that have boss rush equivalents. I'm pretty sure every standard issue MegaMan has a mandatory reunion of -Mans during the final level (and -Womans, for those of you enjoying MegaMan 9). Klonoa has one, Rez has one, Metal Gear Solid too, and even Super Smash Bros. Brawl. Let's take Rez for example. How I love Rez. I heard there was a boss rush mode, I went and unlocked it, I played it with much glee (initially), and then I beat it. Something was missing. Oh, that's right - the rest of the game that was designed to build up to the bosses. I guess it's a cheap shot to use Rez as an example, as we all know by now that the entire game was designed to be played in one continuous session to allow Mizuguchi-san's personal message of l♥ve to flow through the bloodstream and cause a euphoric understanding of the inner workings of the universe, the predicting of the future, and knowledge of how to get him to actually make a sequel. My point is that the bosses, at least in shmups, were designed to push you that extra mile at the end of each level, when your supplies are diminished and you have little left to live for. Taking away that whole energy-draining build-up not only lets you perform much more triumphantly (at first), but it gives you less of a reason to be excited that you finally made it to the next boss.
One of my few counterpoints to the boss rush is in WARNING FOREVER. Those of you familiar know all too well why this stands as a combatant to the despised boss rush; it's because the game was designed from the ground-up to be just that - a rush of bosses. The idea is both executed and enjoyed flawlessly here, as the intent of each boss is to serve as a level that you work through. Blow off a wing here, dodge a vulcan blast there, and ultimately shoot the core for a fantastic explosion (abbridged version for post-level-5 scenarios).
And so, the next time you decide not to play the entire game, but only eat the candy at the end of each trail, I invite you to also go watch Luke blow up the Death Star, Lando blow up the other Death Star, and Vader toss the Emperor to his infinite doom all in a matter of minutes. Again, it's fun at first, but you'll begin to understand why you appreciated them in the first place when you rewatch Greedo shooting first or C-3PO piggybacking Chewy or Ackbar yelling something about tarps.
And here's video of a shmup with a boss rush. Raiden Fighters Jet, but who cares? I'd rather see the full game. Better yet, I should go play the full game. And I will :]
[cross-posted on Gamasutra]