Boss Music

Boss Music is used numerous times in the Kingdom Hearts series to indicate that the current battle is with a boss. Most Boss Music is fast-paced and sends a theme of evil or tension. Usually the same song would be used in different boss battles to show the connection between them, i.e Shrouding Dark Cloud is associated with Heartless Bosses and Squirming Evil is used commonly for Disney Bosses in Kingdom Hearts.

Kingdom Hearts

Awakening

Darkside - Dive into the Heart (Destati)

Destiny Islands

Darkside - Destiny's Force

Traverse Town

Leon - Night of Fate

Guard Armor - Shrouding Dark Cloud

Opposite Armor - Destiny's Force

Wonderland

Queen of Hearts, Card Soldiers and Crank Tower - To Our Surprise

Trickmaster - Shrouding Dark Cloud

Olympus Coliseum

Cloud (Story) - Shrouding Dark Cloud

Cerberus (Story) - Squirming Evil

Hades - Squirming Evil

Rock Titan - The Deep End

Ice Titan - The Deep End

Sephiroth - One-Winged Angel (from Final Fantasy VII)

Deep Jungle

Sabor - Having a Wild Time

Clayton - Having a Wild Time

Clayton w/ Stealth Sneak - Squirming Evil

Agrabah

Pot Centipede - Shrouding Dark Cloud

Cave of Wonders Guardian - Arabian Dreams

Jafar (1st Battle) - Squirming Evil

Jafar (Genie) - Destiny's Force

Kurt Zisa - The Deep End

Monstro

Parasite Cage (1st Battle) - Shrouding Dark Cloud

Parasite Cage (2nd Battle) - Destiny's Force

Atlantica

Ursula - Squirming Evil

Giant Ursula - The Deep End

Halloween Town

Lock, Shock and Barrel - Spooks of Halloween Town

Oogie Boogie (1st Battle) - Squirming Evil

Oogie Boogie (2nd Battle) - Destiny's Force

Neverland

AntiSora - Shrouding Dark Cloud

Captain Hook - Squirming Evil

Phantom - Destiny's Force

Hollow Bastion

Riku (1st Battle) - Scherzo Di Notte

Maleficent (1st Battle) - Squirming Evil

Maleficent (Dragon) - The Deep End

Riku (2nd Battle) - Forze del Male

Behemoth - Destiny's Force

World Terminus

Chernabog - A Night on the Bald Mountain

End of the World

Ansem (1st Battle) - The Deep End

Darkside - Destiny's Force

Ansem (2nd Battle) - Forze del Male

World of Chaos - Guardando Nel Buio

Kingdom Hearts Final Mix

Hollow Bastion

Unknown - Disappeared

Kingdom Hearts: Chain of Memories

Sora Mode

Traverse Town

Guard Armor - Struggle Away

Wonderland

Card Soldiers - To Our Surprise

Trickmaster - Struggle Away

Olympus Coliseum

Cloud - Go For It!

Hades - The Fight for my Friends

Agrabah

Jafar - The Fight for my Friends

Monstro

Parasite Cage - Struggle Away

Halloween Town

Oogie Boogie - The Fight for my Friends

Atlantica

Ursula - The Fight for my Friends

Neverland

Captain Hook - The Fight for my Friends

Hollow Bastion

Maleficent - The Fight for my Friends

Destiny Islands

Darkside - Struggle Away

Simulated Twilight Town

Vexen (2nd Battle) - The 13th Struggle

Castle Oblivion

Axel (1st Battle) - The 13th Struggle

Larxene (1st Battle) - The 13th Struggle

Riku Replica (1st Battle) - The Force in You

Riku Replica (2nd Battle) - The Force in You

Vexen (1st Battle) - The 13th Struggle

Riku Replica (3rd Battle) - The Force in You

Riku Replica (4th Battle) - The Force in You

Larxene (2nd Battle) - The 13th Struggle

Axel (2nd Battle) - The 13th Struggle

Fake Marluxia (1st Battle) - Graceful Assassin

Marluxia (Second Form) (2nd Battle) - Scythe of Petals

Riku Mode

Hollow Bastion

Maleficent - The Fight for my Friends

Traverse Town

Guard Armor - Struggle Away

Agrabah

Jafar - The Fight for my Friends

Monstro

Parasite Cage - Struggle Away

Neverland

Captain Hook - The Fight for my Friends

Wonderland

Trickmaster - Struggle Away

Olympus Coliseum

Hades - The Fight for my Friends

Atlantica

Ursula - Face It!

Halloween Town

Oogie Boogie - The Fight for my Friends

Destiny Islands

Darkside - Struggle Away

Simulated Twilight Town

Riku Replica (2nd Battle) - The Force in You

Castle Oblivion

Vexen - The 13th Struggle

Riku Replica (1st Battle) - The Force in You

Lexaeus - The 13th Struggle

Ansem - Revenge of Chaos

Kingdom Hearts Re:Chain of Memories

Sora Mode

Castle Oblivion

Marluxia (Third Form) - Lord of the Castle

Riku Mode

Destiny Islands

Zexion - The 13th Struggle

Kingdom Hearts II

Roxas

Awakening

Twilight Thorn - Tension Rising

Simulated Twilight Town

Axel (1st Battle) - The 13th Struggle

Axel (2nd Battle) - The 13th Struggle

Sora

Hollow Bastion

Demyx (2nd Battle) - The 13th Dilemma

Radiant Garden

Sephiroth - One Winged Angel (For Final Fantasy VII)

Land of Dragons

Shan Yu - Vim & Vigor

Storm Rider - The Corrupted

Beast's Castle

Possessor/Thresholder - Dance to the Death

The Beast - Tension Rising

Shadow Stalker - Dance to the Death

Dark Thorn - Desire for All That Is Lost

Xaldin - The 13th Dilemma

Underworld

Cerberus - Vim and Vigor

Demyx (1st Battle) - Tension Rising

Pete (1st Battle) - Rowdy Rumble

Hades - The Encounter

Olympus Coliseum

Hydra - Desire for All That Is Lost

Timeless River

Pete (Timeless River) - Rowdy Rumble

Pete (2nd Battle) - Rowdy Rumble

Pete (3rd Battle) - Desire for All That Is Lost

Port Royal

Captain Barbossa and Illuminator - Vim and Vigor

Grim Reaper (1st Battle) - Sinister Shadows

Grim Reaper (2nd Battle) - The Corrupted

Agrabah

Volcanic Lord and Blizzard Lord - Desire for All That Is Lost

Jafar - The Encounter

Halloween Town

Prison Keeper and Lock, Shock and Barrel - Dance to the Death

Christmas Town

Oogie Boogie - The Encounter

Lock, Shock and Barrel - Rowdy Rumble

The Experiment - The Corrupted

Pride Lands

Shenzi, Banzai, and Ed (1st Battle) - Rowdy Rumble

Scar - The Encounter

Shenzi, Banzai, and Ed (2nd Battle) - Rowdy Rumble

Groundshaker - The Corrupted

Space Paranoids

Hostile Program - The Corrupted

Sark - Sinister Shadows

Sark and the MCP -The Encounter

The World that Never Was

Xigbar - The 13th Dilemma

Luxord - The 13th Struggle

Saïx - The 13th Dilemma

Xemnas - Disappeared

Xemnas (Dragon) - Darkness of the Unknown

Xemnas (Dragon) (2nd Battle) - Darkness of the Unknown

Xemnas (Final) - Darkness of the Unknown

Kingdom Hearts

Xemnas (Armor) (1st Battle) - A Fight to the Death

Kingdom Hearts II Final Mix

The Gathering Place

Lingering Sentiment - Rage Awakened

Cavern of Remembrance

Xemnas Data Battles - Disappeared and Darkness of the Unknown

Xigbar, Xaldin, Saïx and Demyx Data Battles - The 13th Dilemma

Vexen, Lexaeus, Zexion, Marluxia and Larxene Data Battles - The 13th Reflection

Axel and Luxord Data Battles - The 13th Struggle

Roxas Data - The Other Promise

The World that Never Was

Organization XIII - The Other Promise

Various

All Absent Silhouettes - The 13th Refection (Agrabah (Vexen), Twilight Town (Lexaeus), Underworld (Zexion), Beast's Castle (Marluxia), Port Royal (Larxene))