At the character selection screen, highlight Hsien-Ko, then press Down.
At the character selection screen, highlight Donovan, then hold Back + LB + RB and press A. You should start the match as Donovan's little sister.
At the character selection screen, highlight Morrigan, then hold Back + LB + RB and press A. You will transform when the match begins.
At the character selection screen, highlight Donovan, then press Down.
At the character selection screen, highlight Morrigan, then press Down.
At the character selection screen, highlight Hsien-Ko, then hold Back + LB + RB and press A. You should be the Talisman when you start the match.
At the character selection screen, hold LB or RB while selecting a character.
At the character selection screen, hold Start while selecting a character.
Accomplish the indicated achievement to get the corresponding number of Gamerscore points: