Bertholdt Fubar, known also as Bertholdt Hoover, hailed from the Liberio internment zone as an Eldian citizen of Marley. His father's debilitating illness drove Bertholdt to join Marley's Warrior program in childhood, seeking financial aid for medical care. This path placed him among Warrior candidates under Commander Theo Magath, training alongside peers including Reiner Braun, Annie Leonhart, Marcel Galliard, and Porco Galliard. Bertholdt displayed exceptional marksmanship and was selected as a Warrior in 843, inheriting the Colossal Titan's power. Physically, Bertholdt stood remarkably tall at 192 cm with a slender build, short dark hair, thin eyebrows, and green eyes; nervous sweating was a frequent trait. His Colossal Titan form towered at roughly 60 meters, featuring exposed musculature, disproportionately long limbs, pillar-like feet, and constant steam emission. Maintaining this form demanded immense energy, and its transformation unleashed explosive blasts. Characterized by quiet reserve, low self-esteem, and self-perceived cowardice, Bertholdt drew criticism from instructor Keith Shadis for lacking initiative while following others, despite noted potential. He developed deep loyalty to Reiner Braun after defending him from Porco Galliard's bullying during Warrior training and harbored unspoken feelings for Annie Leonhart. Though instrumental in devastating attacks, he showed kindness to comrades like Ymir and expressed visible guilt over actions such as abandoning Marco Bott to die. In 845, Bertholdt executed the Paradis Island operation to recover the Founding Titan. He breached Wall Maria at Shiganshina District, enabling a Titan invasion that caused massive casualties. Infiltrating the 104th Cadet Corps with Reiner and Annie, he graduated third in his class. During training, he advised Eren Jaeger on omni-directional mobility gear and admired his determination. Despite forming genuine bonds with cadet peers, Bertholdt described his internal conflict over betrayal as "three years in hell." Bertholdt's demeanor shifted starkly during the Battle of Shiganshina. He adopted a detached resolve, accepting his role as a villain and rationalizing his actions as inevitable in a cruel world. He declared intent to kill former comrades without malice, absolving them of blame. Prioritizing Reiner's rescue over mission protocols, he fought strategically against the Survey Corps. His resolve ultimately fractured; as Armin Arlert's Pure Titan advanced, Bertholdt screamed for Reiner and Annie before being consumed alive. His final moments epitomized his existence: a reluctant warrior retaining humanity amidst catastrophic deeds, dying terrified and calling for the companions central to his life.