He also has his merged hollow form, but it's unlikely that a battle against Aizen would trigger this power. This form came out to balance the amount of Quincy reiatsu, and Aizen doesn't have ...

Off-screen, Aizen fused together the essence of several Soul Reapers to form an artificial Hollow named White, which was intended to bite a Soul Reaper and infect them with Hollow essence ...

Aizen wanted to make Ichigo his potential rival and let the latter take on some of the most serious fights of his life. This will not only help Ichigo transcend his Shinigami and Hollow prowess ...