Aro had his eye on the twins for many years, and decided to wait until they were older to change them. This changed when Aro was forced to slaughter the whole village because the humans believed them to be using witchcraft, and tried to burn them at the stake. Aro was now forced to change them while they were still young. They are now the most valued members of the guard, due to them being extremely powerful. It is said, that they are probably a pair of the most, if not the most powerful vampires in the world, and have the ability to take down vampires twice their size.
Jane is sent out into the castle to bring Edward to the rest of the guard, and Alec takes delight in teasing Jane for bringing back Alice and Bella too. Alec watched as Jane tests her powers on Edward and Bella and does not use his powers. Once Edward, Alice and Bella are permitted to leave, they must wait until midnight to go. Alec went to tell them when they could leave.
his twin Jane appears later. Jane is sent to clean up the newborn army that Victoria created. It is said that only three people came: Jane, Demetri, and Felix.
He alongside his twin, Jane, accompany the rest of The Volturi guard to Forks to deal with the presumed immortal child. Jane and Alec were supposed to use their powers to give The Volturi an advantage. After Jane's powers were unsuccessful due to Bella's shield, Alec tried to use his powers. However, he too was unsuccessful at penetrating Bella's shield.
When Jane became infuriated that her powers were useless on Bella, she prepared to spring and attack Bella. Alec stopped Jane by restricting her.After Renesmee Cullen was proven to be a child between human and vampire, he retreats to Volterra along with the rest of the Volturi.
Special talents Edit
Alec has an extremely powerful gift which is equally powerful as his twin Jane's. He has the ability to cut off a person's senses. He can make them blind, deaf, and numb to any feeling if he wishes to. When he uses his gift, it appears in the form of a clear hazy mist. Unlike Jane's power, Alec can cut off a multiple number of people's senses while Jane can only inflict her power on only one person in her focus.
When he attempted to use it on the Cullens and the vampires they had gathered as witnesses, Sam Uley's pack and Jacob Black's pack, the 'mist' slowly crawled towards the group. Upon hitting Bella's 'shield', it went around it, making Bella's shield look like a bubble of protection (which it was). Alec did not retract his 'mist' for the entire confrontation, constantly looking and probing for holes or weak spots in Bella's shield.
Alec and Jane are believed to be the most powerful, or one of the most powerful vampires in the world, due to their amazing offensive gifts. It is currently unknown if Jane and Alec are skilled at fighting, without the use of their gifts. However, they have been alive for many centuries, and been with the Volturi for the same amount of time, it is sure that they would have picked up some good skills throughout their lifetime.
Other than Alec's special talent, he has common vampiric abilities, such as extreme speed, sharp senses, granite-hard skin, agility and strength.
 Physical description Alec is described as looking a lot like his sister, having pale skin and blood-red eyes, though his lips that aren't as full as his sister Jane's, and he has darker brown hair. As he was changed when he was very young, Alec is described as angelic and beautiful. He has purple-like bruises under his eyes, which change with his level of thirst