Here is the full list of all 15 Heroes of Time 2 - there are Aizack's Return achievements.
Travel to the Temporal Dimension
Use the emblem in Luna Village
Use the emblem in the rocky cave
Use the emblem in Alda
Use the emblem in the lava cave
Use the emblem in the icy cave
Use the emblem in Agaris kingdom
Use the emblem in Aqala
Use the emblem in the Cronos dimension
Use an emblem that send you to the future again
Make the Aarcane Pendant send you to the Cronos dimension
Save the timeline from the hands of Aizack
Defeat Aizack without Arcane Pendant
Finish the game in the looping
Do a 2º looping