Alex is a Mercury adept from the snowy village of Imil. Very little is known about Alex because he isn't seen very often in either game. However, it is known that Alex and Mia grew up together and it heavily hinted that there may have once been a relationship that goes beyond childhood acquaintances between the two, evidenced by the remarks that can be seen by reading Alex's mind in Jupiter Lighthouse: "Even now, I want to run to Mia, to give her my aid...It seems I am weak as well... I suppose I have no choice but to part ways with Agatio and Karst."
It is also speculated that, due to the lack of Mercury adepts in Imil (a village much like Vale and Contigo), Alex and Mia are the last living descendants of the Mercury clan, the clan of adepts that protected Mercury Lighthouse from intruders since the lighthouse's construction.
 Golden Sun
Alex is only a supporting character for the main villains, Saturos and Menardi, as the man who does Saturos and Menardi's bidding by taking the elemental stars from Isaac and Garet but it is first evidenced in Alex's first appearance that he has extraordinary powers even for an adept. Alex is the only adept seen in both games who can Warp at will and levitate without the use of the Teleport Lapis or Hover Jade.
When Isaac's group encounters Alex at Mercury Lighthouse, Mia is astounded to see Alex alive and well after he left Imil in pursuit of his own goals. Mia is more astounded, however, to learn of Alex's new powers (Warp and Levitate), neither of which Mia is ever able to do.
 Golden Sun: The Lost Age
Alex plays a more prominent role in The Lost Age, but his role is essentially the same: to play the supporting role for the game's new villains, Agatio and Karst. However, throughout the game, Alex often pushes Felix's group to hurry to the lighthouses to light them. When questioned, Alex merely states that he would like to see Alchemy alive once more.
His true motives are finally revealed at the end of the game when the Mars Lighthouse is lit and the Wise One reveals that when all four lighthouses are lit, Alchemy's power will gather at the top of Mt. Aleph and anyone bathed in the Golden Sun's light will receive limitless life and power. We cut to a scene of Alex climbing Mt. Aleph, asking the Golden Sun to wait a moment for him to reach the top.
Alex's plan all along was to light the lighthouses so he could gain unlimited power, which he does. Or so he thinks. After receiving the Golden Sun's power, Alex tries to call a storm down on Vale, only to realize to his shock that he can't. Frustrated and angry, Alex demands to know why he cannot summon a storm. The Wise One appears to enlighten Alex, stating that back in the first game when Isaac and Garet first took the Mars Star, the Wise One imbued Isaac with some of the Mars Star's power, so that Alex would not receive the entire power of the Golden Sun. Alex's plan is utterly stopped by the unknowing Isaac. Angry, but confident, Alex confronts the Wise One only to learn that the Wise One speaks the truth. Alex is defeated and immobilized as Mt. Aleph sinks into the ground, burying Alex forever.
 Golden Sun: Dark Dawn
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