Here are some examples:
* Malicious: Harmful or spiteful
* Maladjusted: Poorly adapted to a situation or environment
* Malformation: An abnormal shape or structure
* Malpractice: Negligence by a professional person
* Malcontent: A dissatisfied or rebellious person
It's important to note that "mal-" doesn't always mean "opposite bad or wrong." It can sometimes indicate something bad or wrong, but the context will make the meaning clear.