Laxus Dreyar is an S-Class mage of the Fairy Tail guild and a member of its Thunder God Tribe. He is the grandson of the guild master Makarov Dreyar and the son of Ivan Dreyar, the master of the dark guild Raven Tail. As a child, Laxus was kind, deeply attached to his grandfather, and admired Fairy Tail greatly. His personality shifted after his father was expelled from the guild; he began to suspect that his own reputation was due solely to being Makarov's grandson rather than his own abilities. This insecurity drove him to become arrogant, overbearing, and dismissive of those he considered weak. He often mocked his comrades and demanded personal favors in exchange for help, and he spoke openly about his ambition to become guild master and purge the guild of what he saw as weak members.

During the Fighting Festival arc, Laxus attempted to take control of Fairy Tail by force, using Evergreen's petrification magic and Freed Justine's enchantments to trap and threaten the guild. He also activated the Thunder Palace, a spell that suspended hundreds of lightning-infused lacrima over Magnolia, intending to destroy the town if the guild did not defeat him. In his battle with Natsu Dragneel and Gajeel Redfox, he entered a berserker state, showing a ruthless willingness to harm even his own grandfather. Despite these actions, when Laxus used the spell Fairy Law, it affected none of his guildmates or the townspeople of Magnolia, revealing that he did not truly see them as enemies. After his defeat, he was excommunicated from Fairy Tail. During his departure, he wept in shame as the guild silently assured him they would always watch over him.

Following his expulsion, Laxus underwent significant development. He became more light-hearted and serene, and he developed a genuine fondness for the guild. He accepted full responsibility for his crimes to protect the Thunder God Tribe's membership, and he showed a willingness to sacrifice himself for others. Makarov later entrusted his will to Laxus, recognizing his changed heart. After Fairy Tail temporarily disbanded, Laxus joined Blue Pegasus alongside the Thunder God Tribe, but he returned to Fairy Tail upon its reformation.

Laxus is an artificially created Dragon Slayer. As a child, his father Ivan implanted a Lightning Dragon Lacrima in his body, granting him Lightning Dragon Slayer Magic. This magic allows him to generate, manipulate, and transform into lightning, enabling high-speed movement, powerful melee and ranged attacks, and defensive bodily transformations. He is also a master of Lightning Magic in general, which he can use in a wide variety of offensive and defensive techniques. He later developed advanced forms, including Red Lightning Dragon Mode, acquired during the Alvarez Empire arc, which uses red-black lightning to enhance his speed and power, and Lightning Dragon King Mode, awakened after absorbing the Lightning Dragon King's Dragon Slayer Magic during the events of Fairy Tail: 100 Years Quest. He also learned Clone Magic from Freed Justine and has used the Fairy Law spell, one of Fairy Tail's three great magics. As a Dragon Slayer, Laxus suffers from motion sickness, though he is deeply ashamed of this weakness. His Fairy Tail guild mark is black and located on his left rib cage, surrounded by a large tribal tattoo. He is almost always seen wearing his signature Sound Pod magic headphones and is known for his lightning bolt-shaped scar over his right eye.