A billion-dollar unsolicited bid for an under-performing lender is Yoshitaka Kitao’s boldest move yet to build a fourth megabank in Japan.

The aggressive offer by SBI Holdings Inc.’s maverick chief executive officer caps a two-year pursuit of Shinsei Bank Ltd. with ¥10 trillion ($91 billion) in assets.

Since an initial approach in 2019, Kitao weighed launching a proxy battle to oust CEO Hideyuki Kudo earlier this year, before backing off when regulators balked. Now, he’s hoping a hefty premium will allow SBI to lift its stake in the lender to 48% from 20%, giving him effective control.