This used to be random event Zombie, and as such, its combat level varies depending on your combat level. Having a combat level of 91 plus will trigger a level 159 zombie. These are now discontinued from RuneScape.
Tactics
Turn on protect melee and attack it. Try to have food with you just in case your prayer falls. They are however fairly easy to kill if you have 60 plus defence.
If you would like to report missing/incorrect information, please Submit a Correction, instead of posting a comment. When posting a comment, please be sure that it is helpful and does not violate the terms of service. Comments in violation of the terms of service will be deleted. Users who post abusive comments will be permanently banned.
Your comment has been posted.
When posting a screenshot, please be sure that it features the focus of the current page and does not violate the terms of service. Screenshots in violation of the terms of service will be deleted.