Here is the full list of all 49 WORLD OF FINAL FANTASY achievements. It takes around 50-60 hours to unlock all of the achievements on Windows.
Defeated 30 teams at the Coliseum.
Defeated Ultros in Tometown.
Completed 30 intervention battles.
Learned the location of Castle Exnine.
Teamed up with Gilgamesh to stop the Bahamutian soldier.
Battled 500 times.
Obtained every last Champion Medal.
Won your first Coliseum battle.
Found all of the keys from the Crimson Prophecy.
Recorded a huge number of Mirages in the Mirage Manual.
Mastered your first Mirage Board.
Completed 10 intervention battles.
Got to the bottom of the “phenomenon” at the Coliseum.
Opened 100 treasure chests.
Defeated your first murkrift Mirage.
Recorded a large number of Mirages in the Mirage Manual.
Found the first key from the Crimson Prophecy.
Completed your first intervention battle.
Battled 100 times.
Obtained your first Champion Medal.
Repelled the Bahamutian Army.
Fulfilled a townsperson’s request for the first time.
Imprismed your first Mirage.
Arrived in Grymoire.
Obtained every achievement.
Reached an ending.
Reached the true ending.
Recorded an inconceivable number of Mirages in the Mirage Manual.
Recorded every last Mirage in the Mirage Manual.
Mastered 100 Mirage Boards.
Opened every last treasure chest.
Defeated every last murkrift Mirage.
Found the secret area in every dungeon.
Completed every last intervention battle.
Fulfilled the requests of every last townsperson in need.
Joined forces with Shivalry to defeat the Golden Flan.
Chastised the fugitive Ifreeta.
Brought all seven of the Pleiad back in line.
Added Tamamohimé to your roster.
Defeated the Quacho Queen with one of Lann’s attacks.
Defeated the Undead Princess 10 times.
Defeated the Princess Goblin with the Warrior of Light.
Defeated every last opponent in the Coliseum.
Braved and completed the new dungeons that appeared.
Defeated the Cogna known as XG.
Defeated many foes using any Magitek armor.
Cleared the sky of uncountable einhänders.
Reached the final chamber of the Nether Nebula in record time.
Thwacked a whole bunch of cactuars in a single thrashing.