Humans:
Spearmen: Spearmen > Experienced Spearmen > Veteran Spearmen
Halberdier: Halberdier > Experienced Halberdier > Veteran Halberdier
Militia: Militia > Experienced Militia > Veteran Militia
Warrior: Warrior > Experienced Warrior > Veteran Warrior
Double swordsman: Double swordsman > Experienced Double swordsman> Veteran Double swordsman
Shielder: Shielder > Experienced Shielded > Veteran Shielder
Light cavalry: Light cavalry > Experienced Light cavalry > Veteran Light cavalry
Pegasus rider: Pegasus rider > Experienced Pegasus rider > Veteran Pegasus rider
Knight: Knight > Experienced Knight > Veteran Knight
Lancer: Lancer > Experienced Landed > Veteran Lancer
Gryphon rider: Gryphon rider > Experienced Gryphon rider > Veteran Gryphon rider
Templar: Templar > Experienced Templar > Veteran Templar
Hospitallar: Hospitallar > Experienced Hospitallar > Veteran Hospitallar
Templar knight: Templar knight > Experienced Templar knight > Veteran Templar knight
Hospitallar knight: Hospitallar knight > Experienced Hospitallar knight > Veteran Hospitallar knight
Battering ram: Battering ram > Hardened Battering ram > Reinforced battering ram
Catapult: Catapult > Hardened Catapult > Reinforced Catapult
Trebuchet: Trebuchet > Hardened Trebuchet > Reinforced Trebuchet
Skirmisher: Skirmisher > Experienced Skirmisher > Veteran Skirmisher
Archer: Archer > Experienced Archer > Veteran Archer
Crossbowman: Crossbowman > Experienced Crossbowman > Veteran Crossbowman
Fire archer: Fire archer > Experienced Fire archer > Veteran Fire archer
Slinger: Slinger > Experienced Slinger > Veteran Slinger
Horse archer: Horse archer > Experienced Horse archer > Veteran Horse archer
Axe thrower: Axe thrower > Experienced Axe thrower > Veteran Axe thrower
Ballista: Ballista > Hardened Ballista > Reinforced Ballista
Warship: Warship > Hardened Warship > Reinforced Warship
Destroyer: Destroyer > Hardened Destroyer > Reinforced Destroyer
Catapult ship: Catapult ship > Hardened Catapult ship > Reinforced Catapult ship
Transport ship: Transport ship > Hardened Transport ship > Reinforced Transport ship
Great transport: Great transport > Hardened Great transport > Reinforced Great transport
Orcs:
Uruk axemen: Uruk axemen > Elite Uruk axemen > Master Uruk axemen > Grandmaster Uruk axemen
Uruk hai: Uruk hai > Elite Uruk hai > Master Uruk hai > Grandmaster Uruk hai
Uruk pikemen: Uruk pikemen > Elite Uruk pikemen > Master Uruk pikemen > Grandmaster Uruk pikemen
Uruk archer: Uruk archer > Elite Uruk archer > Master Uruk archer > Grandmaster Uruk archer
Olog hai: Olog hai > Elite Olog hai > Master Olog hai > Grandmaster Olog hai
Goblin spearmen: Goblin spearmen > Elite Goblin spearmen > Master Goblin spearmen
Goblin batrider: Goblin batrider > Elite Goblin batrider > Master Goblin batrider
Merblin harpoonist: Merblin harpoonist > Elite Merblin harpoonist > Master Merblin harpoonist
Merblin gutter: Merblin gutter > Elite Merblin gutter > Master Merblin gutter
Merblin servant: Merblin servant
Some (orcs, humans) are simple name adjustments.Dwarves:
Dwarven short piker: Dwarven short piker > Advanced Dwarven short piker > Supreme Dwarven short piker
Dwarven billman: Dwarven billman > Advanced Dwarven billman > Supreme Dwarven billman
Dwarven halberdier: Dwarven halberdier > Advanced Dwarven halberdier > Supreme Dwarven halberdier
Dwarven maceman: Dwarven maceman > Advanced Dwarven maceman > Supreme Dwarven maceman
Dwarven double axeman: Dwarven double axeman > Advanced Dwarven double axeman > Supreme Dwarven double axeman
Dwarven warrior: Dwarven warrior > Advanced Dwarven warrior > Supreme Dwarven warrior
Dwarven swordsman: Dwarven swordsman > Advanced Dwarven swordsman > Supreme Dwarven swordsman
Dwarven shielder: Dwarven shielder > Advanced Dwarven shielder > Supreme Dwarven shielder
Dwarven axeman: Dwarven axeman > Advanced Dwarven axeman > Supreme Dwarven axeman
Dwarven hammerer: Dwarven hammerer > Advanced Dwarven hammerer > Supreme Dwarven hammerer
Boar lancer: Boar lancer > Advanced Boar lancer > Supreme Boar lancer
Boar rider: Boar rider> Advanced Boar rider > Supreme Boar rider
Boar scout: Boar scout > Advanced Boar scout > Supreme Boar scout
Dwarven priest: Dwarven priest > Advanced Dwarven priest > Supreme Dwarven priest
Dwarven cleric: Dwarven cleric > Advanced Dwarven cleric > Supreme Dwarven cleric
Dwarven axe thrower: Dwarven axe thrower > Advanced Dwarven axe thrower > Supreme Dwarven axe thrower
Dwarven ball thrower: Dwarven ball thrower > Advanced Dwarven ball thrower > Supreme Dwarven ball thrower
Dwarven hand crossbowman: Dwarven hand crossbowman > Advanced Dwarven hand crossbowman > Supreme Dwarven hand crossbowman
Dwarven crossbowman: Dwarven crossbowman > Advanced Dwarven crossbowman > Supreme Dwarven crossbowman
Dwarven repeating crossbowman: Dwarven repeating crossbowman > Advanced Dwarven repeating crossbowman > Supreme Dwarven repeating crossbowman
Dwarven musketeer: Dwarven musketeer > Advanced Dwarven musketeer > Supreme Dwarven musketeer
@Alexander82, @Stratego (dev)