look his streacks
and kills
whit the same persone
Use /report (Iron+) or record and report here: https://reports.cubecraft.net/report
More information on reporting other players can be found here: https://www.cubecraft.net/threads/how-to-use-the-report-system.175577/
(If you're able to, create another report under teaming for the person who is supposedly teaming with the cheater.)