Hi there, Thank you for reaching out to us. We have received reports of this issue you describe experiencing. As per our [url=https://help.bungie.net/hc/en-us/articles/39007140765204-Destiny-2-Known-Issues-and-Vital-Information]Known Issues[/url] list: [quote]Players are unable to complete Altar of Reflection: Catalyst due to one of the bosses staying immune. [/quote] For any updates on this issue, we recommend viewing our Patch Notes as they become available, posted on the [url=https://www.bungie.net/7/en/News]News [/url]page.