Here is the full list of all 44 Legendary Hoplite achievements.
Lose for the first time.
Exhaust 50 times.
Call 300 waves early.
Earn 10000 Coin.
Earn 30000 Coin.
Earn 20 Points.
Earn 40 Points.
Kill 5000 enemies.
Kill 10000 enemies.
Kill 123 pigs.
Deploy 300 Phalanxes.
Phalanxes throw spears to kill 100 enemies.
Use 200 Barrels.
Create 50 firework.
Collapsing Palisades kill 200 enemies.
Create 50 Rocky Talos.
Vinegrasp root 100 enemies.
Build 300 Archer Towers.
Archers trap 100 Beast-typed enemies.
Build 100 Stone throwers.
Deploy 100 Musician.
Build 100 Witches.
Witches put 200 enemies to sleep.
Summon 200 Ghost Warriors, Ghost Archers.
Deploy 300 Cavalries.
Cavalries kick 200 enemies.
Cavalries behead 200 enemies.
Defeat Cerberus for the first time.
Defeat Stheno for the first time.
Defeat Hydra for the first time.
Defeat Ajax for the first time.
Defeat Arachne for the first time.
Defeat Minotaur's Descendant for the first time.
Defeat Talos for the first time.
Defeat Triton God for the first time.
Defeat Charybdis & Scylla for the first time.
Drop 20 Rare items.
Drop 40 Uncommon items.
Equip 4 Legendary items into the battlefield.
Sell 100 items.
Unlock 9 Hero's Passives for every stat: STR, AGI, EDR, LDS.
Use an Level 3 Army for the first time.
Use an Level 4 Army for the first time.
Use an Level 5 Army for the first time.