Here is the full list of all 24 Jagged Alliance Flashback achievements.
Complete the first mission
Complete the Spice questline
Kill 25 enemies
Complete a side mission
Complete all side missions
Find a way to Angetta
Kill the prince and complete the game
Kill 100 Enemies
Kill 500 enemies
Destroy 10 environment pieces
Destroy 50 environment pieces
Destroy 100 environment pieces
Use 5 bandages
Use 25 bandages
Use 50 bandages
Heal 5 mercenaries in doctor mode
Heal 50 mercenaries in doctor mode
Heal 100 mercenaries in doctor mode
Hire 5 Mercenaries
Hire 15 Mercenaries
Hire 50 Mercenaries
Train 5 militia squads
Train 25 militia squads
Train 75 militia squads