Shadow the Hedgehog cheats and cheat codes for Gamecube

Unlock Hidden Vehicles:
Find all 5 keys in Air Fleet - An Air Saucer
Find all 5 keys in Central City - Air Saucer
Find all 5 keys in Digital Circuit - Warp Hole
Find all 5 keys in Glyphic Canyon - Black Arm's Vehicle
Find all 5 keys in GUN Fortress - Milatary Vehicle
Find all 5 keys in Iron Jungle - Tank cannon
Find all 5 keys in Lava Shelter - Air Saucer
Find all 5 keys in Lost Impact - GUN Vehicle
Find all 5 keys in Prison Island - Tank Cannon
Find all 5 keys in Sky Troops - Black Arms' Vehicle
Find all 5 keys in Westopolis - Armoured car

Unlock Hidden Key:
Find all 5 keys in Black Comet - 2 turrets
Find all 5 keys in Circus Park - Extra shooting gallery
Find all 5 keys in Cosmic Fall - Switch that makes ring trails to the end
Find all 5 keys in Cryptic Castle - Shortcut
Find all 5 keys in Death Ruins - Warp Hole
Find all 5 keys in Final Haunt - Turrets
Find all 5 keys in Glyphic Canyon - Black Hawk
Find all 5 keys in Lethal Highway - Large GUN Cannon
Find all 5 keys in Lost Impact - Armored Car
Find all 5 keys in Mad Matrix - Alternate path to a red terminal.
Find all 5 keys in Sky Troops. - Black Volt
Find all 5 keys in Space Gadget - Warp Hole
Find all 5 keys in The ARK - 3 extra lives
Find all 5 keys in The Doom - Opens cage (shortcut to the end of the stage)
Find all 5 keys in The Last Way - Warp Portal

Unlock Gameplay Modes:
Find all 71 "A" rankings. - Expert Mode
Defeat every 6th stage in story mode, and see the hero and dark endings 
for each.  - Last Story

Unlock More Weapons:
Egg Vacuum: Finish story mode as neutral 
Shadow Rifle: Finish Last Story mode 
Omachao Gun: Finish semi hero story mode
Satellite Laser: Finish story mode as bad 
Samurai Sword: Finish story mode as pure evil 
Healer Gun: Finish story mode as pure good 

Library sequences:
D=Dark, Neutral=N, Hero=H

1: Punisment, Thy Name Is Ruin: D, D, D, D, D, D, Dark final Boss
2: Prologue To World Conquest: D, D, D, D, D, D, Hero ending
3: The March To A Darker World: D, N, D, N, H, D
5: Purification Via Ruination: D, D, D, H, D, Dark ending
6: Apogee Of Darkness: D, D, D, H, D, Hero ending 
7: True Soldier Of Destruction: D, D, D, H, N, Dark ending
8: Believe In Yourself: D, D, D, H, N, H 
11: Revenge At Last: D, D, N, D, D, Dark ending 
15: The Nightmare's Insulation: D, D, N, N, D, Dark ending
16: The Nightmare's Sublimation: D, N, N, N, D, H
17: The Loner's Choice: D, D, N, N, N, D
18: Subjugation IN BLACK: D, N, N, N, N, N
27: The Cleansing of Darkness: D, D, H, D, D, D
45: The World's Demise: D, H, D, D, D, Dark ending 
48: Vainglory or Abandonment?: D, H, D, D, N, Hero ending
51: Controller from the Capsule: D, H, D, N, N, D
52: Beyond One's Own Power...: D, Hero. D, N, N, Good.
57: Transcendentalism: D, H, D, H, N, D 
78: Power Of Love: D, H, N, H, H, H
80: Walk My Way: D, H, H, D, D, Hero ending
91: The Rise and Fall Of The ARK: D, H, H, H, D, D
98: Severed Chains: N, D, D, D, H, H
102: Arriving At The Ego: N, D, D, H, N, Hero ending
105: Demise Wrought by Tragedy: N, D, N, D, D, D
111: Soldier Of Grief: N, D, N, N, N, Dark ending
112: Reclaimed Heart: N, D, N, N, N, H
120: Spawn Of The Devil: N, D, D, H, H, Hero ending
121: Black Doom's Scheme: N, D, H, D, D, Dark ending
135: A Vow For The Victims: N, D, H, H, N, D
144: One To Succeed A God: N, N, D, N, D, Hero ending
145: Disappointed In Humanity: N, N, D, N, N, D
146: Faith Taken From Solitude: N, N, D, N, N, N, Hero final Boss
153: Together With Maria...: N, N, D, H, H, Dark ending
154: The Tragedy's Conclusion: N, N, N, D, H, H, Hero ending
155: The Day That Hope Died: N, N, N, D, D, D
159: At Least, Be Like Shadow...: N, N, N, D, H, Dark
160: Seeking A Silent Paradise: N, N, N, D, H, Hero
161: The Lion's Awakening: N, N, N, N, D, Dark ending
162: Identity: N, N, N, N, D, Hero ending
163: An Android's Rebellion: N, N, N, N, N, D
164: A New Empire's Begining: N, N, N, N, N, N, Hero final Boss
165: Bullets From Tears: N, N, N, N, H, Dark ending
166: Journey To Nihility: N, N, N, N, H, H
168: Dr. Eggman's Miscalculation: N, N, N, H, D, H
170: Requiem For The Heavens: N, N, N, H, N, Hero ending
171: Sonic Dethroned: N, N, N, H, H, D 
175: Farewell To The Past: N, N, H, D, N, Dark ending
182: Compensation For A Miracle: N, N, H, N, N, N, Hero final Boss
191: Dark Soldier: N, H, D, D, N, D
195: Birth Of The Dark Soldier: N, H, D, N, D, Dark
203: Perpetual Voyage: N, H, D, H, N, D 
215: Wandering For Eternity: N, H, N, N, N, Dark ending
216: At Vagrancy's End: N, H, N, N, N, Hero ending
220: The Importance of Truth: N, H, N, H, N, Hero ending
225: Solitary Journey: N, H, H, D, N, D. 
228: I Shall Be The One To Judge: N, H, H, D, H, Hero ending
229: Gone With The Darkness: N, H, H, N, N, D
230: The Ultimate Choice: N, H, H, N, D, H
231: I Am The Strongest!: N, H, H, H, H, Dark ending
232: Justice's Awakening: N, H, H, H, H, Hero ending
259: A Heart Bound To The ARK: H, D, N, N, H, Dark ending
262: Steel Combat Boots: H, D, N, H, D, Dark ending
263: Protector Of The Ashen Moon: H, D, N, H, N, Dark ending
266: I Know The Will Of Heaven: H, D, N, H, H 
275: The Reason You Were Born: H, D, Hero N, N, Dark
276: The Dark Part Of The Galaxy: H, D, H, N, N, Hero.
282: Beloved Memories: H, D, H, H, H, H
283: Birth Of A Devil: H, H, D, D, D, D
291: The Doctor's Lie: H, H, D, N, N, D 
309: Funeral Procession In Space: H, H, N, N, N, D
316: The One Who Maria Entrusted: H, H, H, N, H, H
317: A.1's Enlightenment: H, H, H, H, N, D, Dark ending
318: A Dying Empire's Cry: H, H, H, D, D, H 
320: Tear-Soaked Hometown: H, H, H, D, N, Hero ending.
321: Sparks On The Horizon: H, H, H, D, H, Dark ending
322: A Use For A Saved Life: D, N, D, H, D
323: Coffin Of Memories: H, N, H, N, D, D 
324: The Self-Imposed Seal: H, H, H, H, N, H 
325: Pretense in the Mirror: H, H, H, H, H, D 
326: A Missive From 50 Years Ago: H, H, H, H, H, H, Hero final Boss