Turns Red/Playing With

Basic Trope: A video game boss grows more difficult as its health is depleted.
 * Straight: The boss is at half health. Now it breathes fire!
 * Exaggerated: The boss is at half health. Now it literally turns red, flies high into the air, drops nuclear bombs, and takes one-tenth damage from all attacks!
 * One Winged Angel
 * Downplayed: The boss is at half health. Now it can move a bit faster and hit somewhat harder.
 * Justified: The boss's blood is corrosive, and it bleeds over more and more of the stage as it suffers wounds.
 * Alternatively: The attack is very painful to the boss, and he doesn't want to use it unless he really has to.
 * Alternatively: The boss is a Villain With Good Publicity, and the attack would compromise his/her public image. So, s/he uses it only as a last resort.
 * I Am Not Left Handed
 * Inverted: The boss is slowed by its wounds.
 * Subverted: The boss reaches half health and starts breathing fire, but its Breath Weapon is actually less powerful than the attacks it was using before.
 * Double Subverted: The boss's new breath weapon is less powerful than the attacks it was using before. And then the wooden stage ignites!
 * Parodied: The boss sees the hero coming and injures itself, complete with checking its remaining Hit Points, so it can use its best attacks right off the bat.
 * Deconstructed: The boss's increasingly fevered attacks and thrashing around become genuinely moving in their sheer desperation.
 * Reconstructed: The boss thought the fight was a game, but now that it's really hurt it flies into a rage, giving the hero the fight of his life.
 * Zig Zagged: The boss's new breath weapon is less powerful than the attacks it was using before. And then the wooden stage ignites... causing even more damage to the boss. But then it gets down to one quarter health and starts using the really powerful attacks.
 * The boss heals itself periodically and cancels its enraged pattern when it pops back over the HP threshold.
 * Averted: The boss fights at peak capacity throughout the battle.
 * Enforced: "The players expect the game's difficulty to increase over time, so why not reflect that in the boss fights as well?"
 * Lampshaded: "Why don't the monsters I fight ever get weaker when I stab their heads?"
 * Invoked: The boss learns to commit Bloody Murder.
 * Defied: A Duel Boss goes to half health and unleashes a strong attack...then catches himself in anger and stops using the attack, saying that it isn't honorable.
 * Alternatively: The Boss gets a therapist to help him work through his mental block preventing him from fighting to his full ability when not injured.
 * Discussed: "The dragons on that mountain are known for going into an Unstoppable Rage when they lose too much blood."
 * Conversed: "That's the third boss I've faced who gets harder when he's nearly dead!"

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