Here is the full list of all 53 FateEXTELLA achievements.
Obtained all achievements.
Recorded all Mystic Codes in the gallery.
Succeeded 100% completion rate in the gallery.
Raised a Servant's Kizuna level to 30.
Raised 3 Servant's Kizuna level to 30.
Cleared Artoria Pendragon's hidden side mission, then defeated her, on four different stages.
Cleared all stages on VERY HARD difficulty.
Prevented a Sector Trap 30 times.
Defeated a total of 5,000 Aggressors.
Completely cleared Artoria Pendragon's sidestory.
Cleared all Servants' sidestories.
Cleared Artoria Pendragon's hidden side mission, then defeated her, once.
Completely cleared Jeanne D'Arc's sidestory.
Revealed the true name of your Noble Phantasm 20 times.
Completely cleared Elizabeth Bathory's sidestory.
Completely cleared Archimedes' sidestory.
Completely cleared Gawain's sidestory.
Prevented a Sector Trap for the first time.
Completely cleared Lü Bu's sidestory.
Completely cleared Iskandar's sidestory.
Completely cleared Karna's sidestory.
Completely cleared Li Shuwen's sidestory.
Completely cleared Gilgamesh's sidestory.
Upgraded one Install Skill by +20.
Completely cleared Nameless' sidestory.
Completely cleared Cú Chulainn's sidestory.
Completely cleared Medusa's sidestory.
Cleared the Golden Poem arc.
Recorded all Install Skills in the gallery.
Allied with Tamamo no Mae in the Golden Poem arc.
Defeated a total of 1,000 Aggressors.
Cleared the Dawn arc.
Defeated Nero Claudius in the Orchid Poem arc.
Defeated Tamamo no Mae in the Dawn arc.
Cleared the Orchid Poem arc.
Performed 50 Moon Crux/Drives.
Defeated Altera in the Orchid Poem arc.
Conquered a total of 100 sectors.
Performed 200 Extella Maneuvers.
Revealed the true name of your Noble Phantasm for the first time.
Succeeded 25% completion rate in the gallery.
Cleared the Flame Poem arc.
Upgraded one Install Skill by +10.
Defeated Altera in the Flame Poem arc.
Switched with a vice general for the first time.
Defeated Tamamo no Mae in the Flame Poem arc.
Performed a Moon Crux/Drive for the first time.
Equipped an Install Skill for the first ime.
Equipped a new Mystic Code.
Obtained an EX rank in the results.
Cleared the 1st stage of the Flame Poem Arc.
Performed an Extella Maneuver for the first time.