Atlas ( boss ) Atlas is a boss in " Final Fantasy XIII - 2 " . The player can fight it in its weakened state after examining the mysterious device that appears in the Bresha Ruins , or at its full power ; the latter of these two possible battles is much harder . Fighting Atlas in his full power form is required to complete a paradox ending . Defeating Atlas ' s weakened form with a 5 - star battle rating earns the player the Scarlet Medal achievement / trophy . Battle . Weakened Form . Only two of the three primary elements of paradigm tactics are likely to be available to Serah and Noel for this battle . Commando and Ravager may be used , but instead of the Medic role , the player will likely have chosen an extra ATB segment as their first bonus . This forces the player to rely on potions or a Cait Sith Medic , and / or a Pulse Knight Sentinel , to defeat this boss . It is quite possible to achieve a 5 - star rating . Just because Atlas is at a weak state , it should not be underestimated . It will attack with powerful punches and a damaging roar , capable of inflicting Curse on the party and also wounding it . As the player may not have unlocked the Medic role for everyone yet , any Paradigm with Medics will do , but having more is always safer . The party should start the chain gauge in the Cerberus Paradigm as soon as the battle begins and quickly shift into Tri - disaster to fill Atlas ' s chain gauge . The boss will fall over unable to attack once staggered , so the party should immediately shift into Cerberus and deplete its HP . With Atlas ' s HP taken care of , a Cinematic Action will begin . Executing the on - screen prompts clears the battle and defeats Atlas . Full Power Form . The player should wait until Serah and Noel have around 3500 HP each before attempting to beat the boss at its full strength . A recommended Paradigm Pack would consist of an efficient Medic , a good Commando ( Early Peakers such as Dragoon and Orion work well ) , and a Sentinel with high HP . The following Paradigms are recommended : The Bloodguard accessories acquired from chocobo racing also work well here , as well as a good supply of Wound Potions . The battle consist of a regular pattern . Relentless Assault should be used to bring up the enemy ' s chain gauge while it is not attacking , and Cerberus should be used when it is staggered . Whenever Atlas attacks , the party should immediately switch to Tortoise to tank the damage , and then switch to Tireless Charge / Diversity to heal while keeping up the chain gauge . Whenever any party member has HP Critical health , they should immediately switch to Salvation to heal them , and make sure to use a Phoenix Down rather than Raise to revive party members as it is more effective and heals cumulative wound damage . It is also a good idea to quickly switch to Salvation and back to Tortoise in between the enemy ' s successive punching attacks to prevent too much damage . If the player is having difficulty , a sixth Paradigm can be used , Safe Subversion ( SAB / SAB / MED ) , to try and inflict Deshell , Deprotect and even Imperil , despite their low success rate , to improve damage potential and quicken the stagger .