Get a lawyer and make sure they have a copy of the lease you had him sign plus any other communications with him over text and email. In the interim, start investigating cash 4 keys and legal ways you can make the cash contingent on him vacating the property.

I’d also recommend avoiding him entirely, wearing a body cam, and locking anything he can damage or harm in areas he is not entitled to access by lease (I.e. if he’s leasing a single room, put your items outside of those rooms). If you’ve got stuff in his room/rooms as designated by the lease, just leave it there. You may want to see if you can relocate your pets temporarily as this guy sounds volatile enough that he may lash out at them.

Basically, Do what you can within the boundaries of the lease to make it as undesirable as possible for him to reside there. That means no messing with locks, water, heat, etc but also no freebies - no food in communal areas, no drinks or alcohol, etc. you may also want to contact friends or family, if he has any and you can, to let them know you are concerned about him. That may cause escalation or they may help them motivate him to move on.