Here is the full list of all 58 Marvel: Ultimate Alliance 2 achievements.
Stop a convoy.
Complete all Power training goals on the Stats page.
Rescue a hideout.
You or other players on your team must destroy 250 health containers.
Choose a side.
Defend your leaders.
Protect a city.
Perform 10 revivals.
Crash a castle.
Topple a dictator.
Raid a hideout.
Defend a convoy.
Ambush your opponents.
Fight back an ambush.
Repay a favour.
Break and enter.
Free a country.
Finish what you started.
Defeat all Act II and III missions as a Pro-Registration team.
Defeat all Act II and III missions as an Anti-Registration team.
Defeat all Act I missions on Legendary Difficulty.
Defeat all Act II missions on Legendary Difficulty.
Defeat all Act III missions on Legendary Difficulty.
Complete a map in Co-Op.
Complete 8 maps in Co-Op.
Complete 24 maps in Co-Op.
Complete all optional mission objectives.
Defeat 12 mission bosses on Super Heroic or Legendary Difficulty without revival or map reload.
Defeat 25 maps on Super Heroic or Legendary Difficulty without revival or map reload.
Perform all 5 recommended training Fusions in Latveria.
Perform 10 Fusions with another player-controlled hero in a Co-Op game.
Earn 20 high scores for each type of Fusion: Targeted, Guided, and Clearing.
Perform all Fusions by combining every available pairing of 24 heroes.
Have 10 special conversations between characters with a history while in an HQ map.
Unlock 23 alternate costumes.
Collect 50 Team Boosts.
Collect 125 Team Boosts.
Collect 200 Team Boosts.
Collect 30 Audio Logs.
Collect 125 Dossiers.
Collect 10 Concept Art Bundles in HQ maps.
Correctly answer 15 Trivia questions.
Score 30 Trivia Fusions.
Earn all Trivia rewards.
Earn Mission Succeeded on a Simulator Mission in Co-Op and return to the Simulator menu.
Earn 4 Bronze Medals from Simulator Missions.
Earn 8 Silver Medals from Simulator Missions.
Earn 12 Gold Medals from Simulator Missions.
Complete all melee training goals listed on the Stats page.
Complete all combat mastery goals listed on the Stats page.
Progress through "Insidious Alliance without breaking any Health Containers"
Complete "Escort Duty" without destroying any turrets.
Defeat 75 foes in "Balance"
Defeat "Overload" with the X-Men.
Throw all the proximity mines in "Balance".
Complete "Insidious Alliance" with all four heroes alive.
Defeat 2 foes within 10 seconds in "Insidious Alliance."
Complete "Escort Duty" without disabling any floor hazards.