Answer: He had paranoia and his mental health quickly deteriorated.
Explanation: In 1558 he suffered a sudden spiral of his mental health which led him to do even more terrible acts.
Answer: 2 He gained lands and support in a brutal way.
Explanation: He created a centrally controlled government (a government reliant on the country's leader.)
Answer 3: He killed many and his own son.
Explanation: He killed his son because his son's wife was pregnant because of the clothes she wore. He beat her up because of it. His son later argued about the beating. Because Ivan was mad, he killed him with his staff.
There is an art reference for the last one.