Arin
Beat Pangya Festa with Kooh.
(Thanks to BleedingHart)

Brie
Beat Arin’s first Pangya Festa.
(Thanks to BleedingHart)

Cecilia
Beat Pangya Festa with Hana or Uncle Bob.
(Thanks to BleedingHart)

Dolfini
Complete the first Pangya Storyline with Kooh.
(Thanks to BleedingHart)

Kaz
Beat Arin’s final storyline. To access this storyline, beat the first storyline with everyone but Kaz, and wear Arin’s Magic School Uniform.
(Thanks to BleedingHart)

Kooh
Beat Pangya Festa with Max.
(Thanks to BleedingHart)

Lola
Complete the first Pangya Storyline with Uncle Bob.
(Thanks to BleedingHart)

Max
Beat Pangya Festa with Cecilia.
(Thanks to BleedingHart)

Pipin
Complete the Tutorial.
(Thanks to BleedingHart)

Quma
Complete the first Pangya Storyline with Hana.
(Thanks to BleedingHart)

Tiki
Complete the first Pangya Storyline with Max.
(Thanks to BleedingHart)

TitanBoo
Beat Cecilia in Arin’s first Pangya Festa.
(Thanks to BleedingHart)

Uncle Bob
Beat Pangya Festa with Scout.
(Thanks to BleedingHart)

Reach M. Bison (Vega) without Battling CPU
Select Arcade Mode normally. When you start your fight press Start on controller 2. Then select for the second player the same fighter the CPU was using and beat it. Repeat this until you find M. Bison (Vega).
(Thanks to Arc_77)

Password
When you get to the end of Level 4 where the robot asks for a password, enter: 747.
(Thanks to Anastasia)

Borg (Skirmish Mode)
Beat Klingon Campaign (Easy).
(Thanks to Klingon #1)

Borg Unicomplex (Star Trek Voyager)
Complete Campaign with the Cardassians.
(Thanks to Klingon #1)

Federation Skirmish Ships
Complete Campaign with the Federation.
(Thanks to Klingon #1)

Sha Ka Ree (Star Trek V)
Complete Campaign with the Breen.
(Thanks to Klingon #1)

Talos IV
Complete Campaign with the Romulans.
(Thanks to Klingon #1)

Xindi Skirmish Ships
Complete Campaign with the Dominion.
(Thanks to Klingon #1)

Alternate Costumes
Beat the game once.
(Thanks to Viktor)

Unlock 3rd Weapon for Each Character
Complete the quests following, after Chapter 5.
(Thanks to Viktor)

Unlock 4th Weapon for Each Character
Reach a Paladin, Master and final rank for your quest.
(Thanks to Viktor)

80s Boulevard
Beat Babylon Story.
(Thanks to Cherry xXx)

90s Boulevard
Beat Babylon Story.
(Thanks to Cherry xXx)

Amigo
Clear all Missions in Story mode.
(Thanks to Cherry xXx)

Angel / Devil Gear
Complete the Heroes Story.
(Thanks to Cherry xXx)

Billy Hatcher
Clear all Missions in Story mode.
(Thanks to Cherry xXx)

Blaze
Beat Babylon Story.
(Thanks to Cherry xXx)

Chaos Emerald Gear
Get Extreme Rank on all Missions in Story mode.
(Thanks to Cherry xXx)

Cream the Rabbit
Beat Team Sonic’s Story.
(Thanks to Cherry xXx)

Eggman
Beat Babylon Story.
(Thanks to Cherry xXx)

Ending Cinema
Beat Babylon Story.
(Thanks to Cherry xXx)

Insert Cinema
Beat Babylon Story.
(Thanks to Cherry xXx)

MAG Gear
Clear all Missions in Story mode.
(Thanks to Cherry xXx)

NiGHTS
Clear all Missions in Story mode.
(Thanks to Cherry xXx)

Opening Cinema
Start the Heroes Story.
(Thanks to Cherry xXx)

Rouge the Bat
Beat Team Sonic’s Story.
(Thanks to Cherry xXx)

SCR-GP
Beat Babylon Story.
(Thanks to Cherry xXx)

SCR-HD
Beat SCR-HD during a Free Race.
(Thanks to Cherry xXx)

Shadow the Hedgehog
Beat Team Sonic’s Story.
(Thanks to Cherry xXx)

Silver
Beat Babylon Story.
(Thanks to Cherry xXx)

World Grand Prix Mode
Beat Team Sonic’s Story.
(Thanks to Cherry xXx)

Level Select
Go to the Press Start screen and enter: B, A, Right, A, C, Up, Down, A. On the Main screen, press the Start Option and the Level Select will appear next.
(Thanks to Utz)

Cheat Gnome
While on a Lot, quickly press B, Z, Up, Down, B to spawn the Cheat Gnome. The Cheat Gnome appears at different locations, depending on which island you are on. Find the Cheat Gnome, then enter one of the following:
Add One to Skill - Quickly press 2, Up, Right, Z, Right.
All Crafting Resources - Quickly press A, A, Down, Down, A.
All Motives - Quickly press -, +, Z, Z, A.
All Plans - Quickly press +, +, -, -, Z.
Maximum Current Food and Resources - Quickly press Left, Right, Left, Right, A.
Maximum Relationships - Quickly press Z, +, A, B, 2.
Vest and Tanktop - Quickly press Z, Z, A, Z, 2.
(Thanks to Dader_9665)

Unlimited Power for All Characters
Enter the code while in the “Extras” menu screen: +, Left, Right, +, -, Z.
(Thanks to BartMan)

Unlock all Cliches
Enter the code while in the “Extras” menu screen: Left, -, Right, +, Right, Z.
(Thanks to BartMan)

Unlock all Movies
Enter the code while in the “Extras” menu screen: -, Left, -, Right, +, C.
(Thanks to BartMan)

Battle Select
While the Sega logo is on screen, enter: Up, Down, Up, Down, Left, Right, Left, Right, Up, Right, Down, Left, B, C, B, C, B, C.
(Thanks to NitroVamp)

Change Characters Names
After selecting the name for the main character, hold Start as you choose “End.” Another name screen will pop up for another character.
(Thanks to NitroVamp)

Chaz
When back in Grands Island, go to back to Yeel and play the piano.
(Thanks to NitroVamp)

Claude
After freeing Moun, find an arm of a golem laying around the top left side of town and get it. Then, find a golem in the secret road leading to Grans.
(Thanks to NitroVamp)

Eric
Go to Creed Mansion after Oddler has become evil.
(Thanks to NitroVamp)

Karna
Go to Creed Mansion after Oddler has become evil.
(Thanks to NitroVamp)

Kiwi
Talk to Kiwi at the empty house before departing by ship from Grans Island.
(Thanks to NitroVamp)

Randalf
Go to Creed Mansion after Oddler has become evil.
(Thanks to NitroVamp)

Secret Configuration Mode
While the Sega logo is on screen, enter: Up, Down, Up, Down, Left, Right, Left, Right, Up, Right, Down, Left, Up, B.
(Thanks to NitroVamp)

Sheela
When returning to Grans Island, go visit the Monk’s Monastery. Make your way to the back of the monastery where you see a waterfall.
(Thanks to NitroVamp)

Skreech
Talk to a baby bird learning how to fly, and when leaving Bedoe, have him fall on you by standing on the right spot (he’ll join you later on).
(Thanks to NitroVamp)

Taya
After defeating Zalbard in Mitula’s Shrine, go investigate a stone figure that looks like a person turned to stone.
(Thanks to NitroVamp)

Tyrin
Go to Creed Mansion after oddler has become evil.
(Thanks to NitroVamp)