Hints: Things to Achieve:
Complete each achievement to receive the allotted gamerscore:
All-star Team-up  - Completed a Story issue in Co-op mode.
Secret Origin  - Fully upgrade any skill.
Silver Aged  - Sustained a 6x multiplier for 60 seconds.
Shadow Artist  - Assassinate 50 enemies while invisible.
Gutter King  - KO'ed 100 enemies by throwing them against the panel edges.
Epic Crossover  - Completed 5 Story issues in Co-op mode.
Bagged and Boarded  - KO'ed 50 enemies with thrown objects.
Golden Aged  - Earned 75K points in Survival mode.
Femme Fatale  - Unlocked Lori's entire skill tree.
Pristine Mint  - Completed a full issue without taking any damage.
Liver Thief  - Unlocked Rick's entire skill tree.
Squarebound Saga  - Defeated the final boss.