Here is the full list of all 100 Gladiator Manager achievements.
Hire a new figher
Achieve a battle rating of 10
Have a fighter reach level 1
Inflict a second injury to the same body part
Land a hit with at least 300 damage
Win a fight
Win 1v1 with a Barbarian
Win a match without so much as a scratch
Win ten fights
One fighter wins five fights
One fighter wins ten fights
One fighter wins twenty fights
Promoted to Division 4
Promoted to Division 3
Promoted to Division 2
Promoted to the top division
Win the League!
Win the Cup!
Beat a team from a higher division in the Cup
Hire or train a fighter with an attribute at 100 (except speed, stamina, recovery)
Win a 1v1 fight with the player-fighter
Win a 1v1 fight with class advantage
Win a 1v1 fight despite class disadvantage
Kill an opposing fighter
Finish a battle with 100% defence (at least 10 defences)
Finish a battle with 100% attack (at least 10 attacks)
Win a fight on the first turn
Get to Solid (80) Popularity
Get to Known (50) Reputation
Get to Famous (80) Reputation
Get to Fanatic (90) Popularity
Get to World Famous (90) Reputation
Who are they? (<8 Reputation)
Decapitate an opponent
Kill an opponent with a precise strike
Successfully pull off a combination move
Have a fighter battle on despite dropping to rock bottom morale
Win 1v1 with a Rogue
Win 1v1 with a Gladiator
Win 1v1 with a Leader
Win 1v1 with a Retarius
Win 1v1 with a Defender
Win 4v4 with 4 fighters of the same class
Have an enemy bleed out when fighting with a Rogue
Crush an enemy's skull when fighting with a Barbarian
Disarm an enemy when fighting with a Gladiator
Inspire (perk ability) the team in a 4v4 match with a Leader
Reach 90 control when fighting with a Retarius
Defend allies to left and right in a single turn with a Defender
Have a fighter reach level 2
Have a fighter reach level 3
Have a fighter reach level 4
Have a fighter reach level 5
Have a fighter reach level 6
Increase an attribute by 8 or more when choosing a perk
Increase advantage over a particular class to 50%+ with perks
Increase advantage over a particular class to 75%+ with perks
Increase advantage over a particular class to 100%+ with perks
Acquire class advantage over three different types of class using random perks
Win a 4v4 match without losing any fighters
Win a match without any damage to armour
Win a fight by forcing a yield without any injury
Knock an enemy over in a charge
Destroy an enemy armour part in one blow
Enter into a Barbarian Rage
Use the Rogue Side Step move
Use the Gladiator Press skill
Use the Retarius Shepherd skill
Use the Gladiator Distract skill
Use the Leader's Angled Attack skill
Use the Retarius' Pin Weapon skill
Use Barbarian's Shoulder Barge skill
Use the Rogue's Trip skill
Use the Gladiator's Pommel skill
Use the Leader's Sun skill
Use the Retarius' Tangle skill
Use the Defender Taunt skill
Use the Barbarian's Shatter Shield skill
Use the Rogue's Forearm Slash skill
Use the Leader's Forum Up skill
Use the Defender's Entrench skill
Have a Defender's Aegis passive skill activate
Use the Barbarian's Massacre skill
Use the Rogue's Disappear skill
Use the Gladiator's Zero In skill
Have a fighter get to a 5 match win streak
Have a fighter get to a 10 match win streak
Have a fighter get to a 5 match loss streak
Have a fighter get to 5 kills
Have a fighter get to 10 kills
Have a fighter inflict 15 injuries
Have a fighter inflict 30 injuries
Have a single fighter survive 10 injuries
Have a single fighter survive 20 injuries
Have a fighter on 50+ average damage dealt after at least 5 battles
Have a fighter with a hit ratio of 80%+ after at least 5 battles
Have a fighter with a defence ratio of 80%+ after at least 5 battles
Have a fighter deal at least 5,000 damage over a career
Have a fighter deal at least 10,000 damage over a career
Have a fighter suffer at least 2,000 damage over a career