Here is the full list of all 26 Exploria Playtest achievements.
Speak to King Avner for the first time.
Defeat Lucifer.
Collect 15 Spyder's eggs for Javin.
Collect 15 Wolf' teeth for Javin.
Collect 15 Gryffon's feather for Javin.
Collect 15 Troll's mucus for Javin.
Collect 15 Icy Troll's mucus for Javin.
Get the Silver medal in the Arena.
Complete all the Arena stages.
Defeat Itzamna
Defeat the Desert Dragon.
Bring back the fisherman lost treasure map.
Bring 25 feathers to King Herren.
Defeat the Dark Knight.
Complete the 1st challenge for Fabio.
Complete the 2nd challenge for Fabio.
Complete the 3rd challenge for Fabio.
Help Queen Simone preventing the coup.
Possess a Gold piece of equipment.
Obtain the strongest shield.
Obtain the strongest weapon.
Deliver Ali's treasure.
Discover all locations in the game.
Have 10.000 gold with you.
Defeat Vulcan.
Complete all missions for King Avner.