Unlockables

Soul Calibur IV Guide - Unlockables

Characters

Algol - Defeat in Story Mode (using Astaroth, Cassandra, Cervantes, Darth Vader, Kilik, Mitsurugi, Rock, Setsuka, Sophitia, Talim, The Apprentice, Xianghua, Yoda, Yoshimitsu, Zasalamel, Angol Fear, Ashlotte, Kamikirmusi, Scheherazade, or Shura).
Amy - Purchase for 4000 Gold.
Cervantes - Purchase for 4000 Gold.
Lizardman - Purchase for 4000 Gold.
Rock - Purchase for 4000 Gold.
Seong Mi-na - Purchase for 4000 Gold.
Setsuka - Purchase for 4000 Gold.
Sophitia - Purchase for 4000 Gold.
Talim - Purchase for 4000 Gold.
The Apprentice - Beat Arcade Mode with Yoda (X360) or Darth Vader (PS3)
Yoshimitsu - Purchase for 4000 Gold.
Yun-Seong - Purchase for 4000 Gold.
Zasalamel - Purchase for 4000 Gold.

Bonus Characters

Angol Fear - Defeat in Story Mode (using Algol, Darth Vader, Kilik, The Apprentice, Zasalamel, or Scheherazade).
Ashlotte - Defeat in Story Mode (using Lizardman, Maxi, Rock, Sophitia, Talim, or Angol Fear)
Kamikirmusi - Defeat in Story Mode (using Amy, Cassandra, Mitsurugi, Tira, Xianghua, Yun-Seong, or Shura).
Scheherazade - Defeat in Story Mode (using Hilde, Nightmare, Siegfried, Voldo, Yoda, Yoshimitsu, or Ashlotte).
Shura - Defeat in Story Mode (using Cervantes, Ivy, Raphael, Seong Mi-Na, Setsuka, Taki, or Kamikirmusi).

Stages

Phantom Pavilion ~ See Saw - Acquire the Floor 14 treasure chest in the Tower of Lost Souls mode (perform 3 Guard Breaks).
Other Stages - Complete the Story Mode multiple times.

Equipment

Equipment Set 1 - Acquire 5 Honors.
Equipment Set 2 - Acquire 10 Honors.
Equipment Set 3 - Acquire 15 Honors.
Equipment Set 4 - Acquire 20 Honors.
Equipment Set 5 - Acquire 25 Honors.
Leviathan and Voodoo Sets - Acquire 30 Honors.

Note: All equipment (and that includes equipment found in the ToLS treasure chests) are available for purchase once 30 Honors have been acquired.