With servers updated from Patch 10.0.0 to Patch 10.0.2 this week, players have noticed Legacy raid bosses have more health than before.
Aggramar had 9.07 million health before the change compared to 13.05 million this week. Argus had 6.35 million last week compared to 9.57 million this week.
Some players can no longer solo Argus as of the Evoker patch.
The buff also appears to target other Legion raids and Battle for Azeroth content. Blizzard most likely made changes to scaling and forgot this would negatively impact Legacy raids.