The OSRS Wiki’s world-firsts table for Hardcore Worlds credits Lunny HCW with the first 99, in Firemaking, on 6 November 2026. On 7 November the official hiscores show the character with 13,034,793 Firemaking experience, just past the 13,034,431 a 99 needs, at a total level of 565.
Firemaking is the obvious first 99 on a one-life mode: nothing in it can kill you, and Wintertodt, where most players train it, is one of the activities with its own Hardcore worlds.