Hello there, Thanks for the report. There is an issue where the totem-launched Oblation mission variants were removed from Fireteam Finder, and notes that the portal versions were not meant to appear there until the relevant mission unlock state was met. For the boss mechanic itself, the encounter flow calls for the boss to go immune, wizards to move into side rooms, an Ecstatic enemy to be defeated for the soulfire buff, and that buff to be dunked at the brazier the boss is using before damage starts. I also found a separate issue where the first soulfire dunk had a longer-than-expected delay before the boss shield dropped, which could make the damage phase feel inconsistent. If you're still seeing the vents or damage transition fail after completing that sequence, please include a video showing the full first phase through the dunk and the boss response.