The 2012-13 campaign delivered a glorious and immediate return to the 2. Bundesliga for Arminia Bielefeld as Die Arminen clinched promotion with a spectacular second-place finish in the 3. Liga. Leading the charge was the towering striker Fabian Klos, whose 20 goals proved decisive in a campaign built on relentless attacking pressure and home dominance. It was a triumphant year that marked the club's vital immediate bounce back from the third tier and remains a cherished chapter in Die Arminen's tumultuous modern history.